Date   
Re: Bring back the UDRC, alongside the DRAWS?

Steve Stroh
 

Disclaimer: Although I know the individuals of NW Digital Radio
personally, the following are my personal comments - not vetted,
approved, or even discussed with anyone at NWDR. I've followed this
"next generation packet radio" space pretty closely for a lot of years
now. Thus I think I have some perspective.

I applaud NW Digital Radio for evolving the UDRC into the UDRC II, the
DRAWS board, and eventually the packaged DRAWS. It's HARD to evolve a
product, for the reasons we're seeing in this thread. It's DAMN HARD
to evolve a product as a small, shoestring company.

My perception (perhaps they've actually said this - don't remember) is
that NWDR kind of stumbled into this market. Recall that the UDRC was
originally intended to create a controller for the Yaesu DR-1X
repeater to add D-STAR capability to it. Quite apart from that
"science project", it turns out, the UDRC met a need in Amateur Radio
for a well thought out "sound card modem" interface for the Raspberry
Pi.

It's notable that the UDRC used the normal communications methods for
Raspberry Pi that other interface boards (HATs) do, rather than the
much easier method of connecting sound card modems via USB. USB is
really nice, easy, simple, cheap... when it works, but sometimes it
doesn't, especially for very cheap consumer devices like sound cards.

It's also notable that the UDRC and its successors were (eventually)
supported under the native Raspberry Pi Linux (Rasperian) and it (most
relevant to me) is capable of 9600 bps FSK operation, which most sound
card modems are not. As NWDR went along with UDRC, they collected a
list of "wants" and "don't wants" for the product, and when it came
time for another production run, they chose to do the hard thing and
evolve the design with the long term goal of making it an "appliance".
That's tough, but it's worth doing.

In their market research leading to the final spec of DRAWS, they
ASKED their customer base if they wanted DRAWS to incorporate a GPS
receiver as standard and named an approximate price. Most of the
respondents said that they were willing to pay a small premium to have
GPS as a standard feature. It will be very, very interesting to see
what the software authors can do when they can assume the presence of
a GPS, including a stable time base. It was kind of an either / or
decision for them; again they can't afford to support and stock
different versions of the same product.

I agree with NWDR's vision - to make a turnkey, packaged DRAWS
available via normal Amateur Radio retail channels, to finally
displace the now very tired legacy TNCs that are still being sold
(much as I love them). It's going to take QUITE an effort to get DRAWS
out into the real world of Amateur Radio as opposed to reaching and
supporting us early adopters who found NWDR largely because we were
looking for such a product and largely self-support (such as these
lists).

Despite appearances :-) NWDR is a very small operation - they can't
afford to support multiple versions of the same product. Thus, they
have to FOCUS.

Godspeed Bryan, Basil, Anna, John, and Dennis! Can't wait to see
what's next from you folks!


Thanks,

Steve Stroh N8GNJ

PS - I also applaud NWDRs secondary, stealth mission - to get Amateur
Radio back into an experimental, "advance the state of the radio art"
mode by embedding a relatively inexpensive open source hardware
platform and most importantly, Linux. This is exactly the kind of
platform that Amateur Radio needs to be perceived as relevant to those
who we need to attract if Amateur Radio will continue beyond the
current generation.

--
Steve Stroh (personal / general): stevestroh@...

Re: Bring back the UDRC, alongside the DRAWS?

rdelowrey@...
 

Bryan

I purchased one of your ThumbDV's several months back. What is the best software to use with this product? Thanks!

Richard DeLowrey KN4JWK

Sent from Rick's IPad

On Dec 7, 2018, at 11:00 AM, Bryan Hoyer <@K7UDR> wrote:


Making 2 products causes inventory issues and makes both more expensive.

After we launched the ThumbDV we still get a couple of requests per year for the PiDV but the economics don’t work out.

We spent a lot of time deciding on the GPS. With the UDRC one could add a USB GPS but that wouldn’t give you PPS, which is arguably not a necessity for Ham Radio but is pretty cool. DRAWS is also a 4 layer Board with additional features; ADC, serial port, and Expansion connector, which increases Ir’s cost.

We even did a survey and found that a majority of responders preferred the on board GPS.

By Comparison the popular Signal Link USB with Cable is $129.95 and has only 1 Radio Port and no GPS.

The best way to save Money is to do a group buy:

5% for 5 units 10% for 10. You can mix DRAWs and ThumbDV in the order.

Use coupons:

club5

club10

Re: Compass udrc kernel panic

Basil Gunn
 

Curt, WE7U <curt.we7u@...> writes:

On Thu, 6 Dec 2018, Annaliese McDermond wrote:

If you?d like to know my offhand guess as to what?s happening, I?d
guess that Chromium is trying to do a broadcast to all interfaces for
some reason. Once you load the ax25 stack, the packet modem becomes
a network interface. This broadcast packet is probably triggering a
bug in the ax25 stack due to it having some sort of freaky address
(or more accurately no address) by the time it gets there. But this
is just a wild guess from hearing the symptoms.
Check Samba as well if it's loaded and running. It's a known
contributor to "talk to all interfaces" problems.
When I bring up an AX.25 machine I always install iptables & block the
following 3 addresses on both ax0 & ax1 interfaces. I noticed these
addresses being broadcast/multicast while looking at a traffic spy of my
RF interfaces.

iptables -A OUTPUT -o ax0 -d 224.0.0.22 -p igmp -j DROP
iptables -A OUTPUT -o ax0 -d 224.0.0.251 -p udp -m udp --dport 5353 -j DROP
iptables -A OUTPUT -o ax0 -d 239.255.255.250 -p udp -m udp -j DROP

iptables -A OUTPUT -o ax1 -d 224.0.0.22 -p igmp -j DROP
iptables -A OUTPUT -o ax1 -d 224.0.0.251 -p udp -m udp --dport 5353 -j DROP
iptables -A OUTPUT -o ax1 -d 239.255.255.250 -p udp -m udp -j DROP

224.0.0.22 is used for IGMPv3 (multicast) protocol
224.0.0.251 is Bonjour/mDNS request coming out of the Avahi daemon
239.255.255.250 is Simple Service Discovery Protocol (SSDP) for uPNP
detection

I agree with Curt that Samba & dropbox will broadcast on all
network addresses but you can fix both of these with proper
configuration of the app.

/Basil

Re: Bring back the UDRC, alongside the DRAWS?

 

Yes, the custom cable will work. You may have to change the alsamixer settings to get the correct audio input as DRAWS has an analog mixer in the front end to select Audio or Discriminator. Seeing as HF rigs don’t have discriminator you need to set alsamixer ti IN_2 instead of the default IN_1 as on the UDRC.

Send me your cable spec and I’ll check it. I have a KX3 Online with DRAWS in my shack.

Yes DRAWS can replace a SignalLink. Now I’m not bashing the SignalLink but the transformer coupled audio prevents doing 9600 FSK on the High End and 4800 GMSK on the Loe end.

On Dec 7, 2018, at 9:03 AM, ve7fmn@... wrote:

OK, so then it begs the question, two actually...
I had a custom cable made to interface between the UDRC-2 and my KX3. Will that cable work with my new to me DRAWS?
Can the DRAWS replace a signalink USB in additional to all of the other cool things it does?
PS, mine arrived day before yesterday, thank you, and I was thoroughly spanked by Canada customs and Canada Post (not thank you).


-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On Behalf Of Bryan Hoyer
Sent: Friday, December 7, 2018 8:01 AM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?


Making 2 products causes inventory issues and makes both more expensive.

After we launched the ThumbDV we still get a couple of requests per year for the PiDV but the economics don’t work out.

We spent a lot of time deciding on the GPS. With the UDRC one could add a USB GPS but that wouldn’t give you PPS, which is arguably not a necessity for Ham Radio but is pretty cool. DRAWS is also a 4 layer Board with additional features; ADC, serial port, and Expansion connector, which increases Ir’s cost.

We even did a survey and found that a majority of responders preferred the on board GPS.

By Comparison the popular Signal Link USB with Cable is $129.95 and has only 1 Radio Port and no GPS.

The best way to save Money is to do a group buy:

5% for 5 units 10% for 10. You can mix DRAWs and ThumbDV in the order.

Use coupons:

club5

club10




Re: Bring back the UDRC, alongside the DRAWS?

ve7fmn
 

It’s the one Mr. Churchward made. I do not have a schematic. One end goes into the UDRC2 the other into a TRRS connector as used by KX3.

-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On Behalf Of Bryan Hoyer
Sent: Friday, December 7, 2018 5:28 PM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?

Yes, the custom cable will work. You may have to change the alsamixer settings to get the correct audio input as DRAWS has an analog mixer in the front end to select Audio or Discriminator. Seeing as HF rigs don’t have discriminator you need to set alsamixer ti IN_2 instead of the default IN_1 as on the UDRC.

Send me your cable spec and I’ll check it. I have a KX3 Online with DRAWS in my shack.

Yes DRAWS can replace a SignalLink. Now I’m not bashing the SignalLink but the transformer coupled audio prevents doing 9600 FSK on the High End and 4800 GMSK on the Loe end.

On Dec 7, 2018, at 9:03 AM, ve7fmn@... wrote:

OK, so then it begs the question, two actually...
I had a custom cable made to interface between the UDRC-2 and my KX3. Will that cable work with my new to me DRAWS?
Can the DRAWS replace a signalink USB in additional to all of the other cool things it does?
PS, mine arrived day before yesterday, thank you, and I was thoroughly spanked by Canada customs and Canada Post (not thank you).


-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On Behalf Of Bryan Hoyer
Sent: Friday, December 7, 2018 8:01 AM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?


Making 2 products causes inventory issues and makes both more expensive.

After we launched the ThumbDV we still get a couple of requests per year for the PiDV but the economics don’t work out.

We spent a lot of time deciding on the GPS. With the UDRC one could add a USB GPS but that wouldn’t give you PPS, which is arguably not a necessity for Ham Radio but is pretty cool. DRAWS is also a 4 layer Board with additional features; ADC, serial port, and Expansion connector, which increases Ir’s cost.

We even did a survey and found that a majority of responders preferred the on board GPS.

By Comparison the popular Signal Link USB with Cable is $129.95 and has only 1 Radio Port and no GPS.

The best way to save Money is to do a group buy:

5% for 5 units 10% for 10. You can mix DRAWs and ThumbDV in the order.

Use coupons:

club5

club10




Re: Bring back the UDRC, alongside the DRAWS?

Budd Churchward
 

I have not made any cables. You probably got yours from Art Miller or Robert Sears. I think it is safe to assume that if the cable worked on your UDRC it is going to work on the DRAWS. Most of us are using standard cables with mini 6 pin DINs on both ends. Your radio doesn't have that connector so a cable had to be made for it. The mini 6 pin DIN is a pretty standard connector with the pins the same from radio to radio. If NWDR made a change to its connectors they would not be compatible with many radios. My DRAWS board came with two standard, off the shelf, cables. They are not doing anything special.

Budd Churchward
WB7FHC

-----Original Message-----
From: ve7fmn@...
Sent: Friday, December 07, 2018 8:36 PM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?

It’s the one Mr. Churchward made. I do not have a schematic. One end goes into the UDRC2 the other into a TRRS connector as used by KX3.


-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On Behalf Of Bryan Hoyer
Sent: Friday, December 7, 2018 5:28 PM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?

Yes, the custom cable will work. You may have to change the alsamixer settings to get the correct audio input as DRAWS has an analog mixer in the front end to select Audio or Discriminator. Seeing as HF rigs don’t have discriminator you need to set alsamixer ti IN_2 instead of the default IN_1 as on the UDRC.

Send me your cable spec and I’ll check it. I have a KX3 Online with DRAWS in my shack.

Yes DRAWS can replace a SignalLink. Now I’m not bashing the SignalLink but the transformer coupled audio prevents doing 9600 FSK on the High End and 4800 GMSK on the Loe end.

On Dec 7, 2018, at 9:03 AM, ve7fmn@... wrote:

OK, so then it begs the question, two actually...
I had a custom cable made to interface between the UDRC-2 and my KX3. Will that cable work with my new to me DRAWS?
Can the DRAWS replace a signalink USB in additional to all of the other cool things it does?
PS, mine arrived day before yesterday, thank you, and I was thoroughly spanked by Canada customs and Canada Post (not thank you).


-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On Behalf Of Bryan Hoyer
Sent: Friday, December 7, 2018 8:01 AM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?


Making 2 products causes inventory issues and makes both more expensive.

After we launched the ThumbDV we still get a couple of requests per year for the PiDV but the economics don’t work out.

We spent a lot of time deciding on the GPS. With the UDRC one could add a USB GPS but that wouldn’t give you PPS, which is arguably not a necessity for Ham Radio but is pretty cool. DRAWS is also a 4 layer Board with additional features; ADC, serial port, and Expansion connector, which increases Ir’s cost.

We even did a survey and found that a majority of responders preferred the on board GPS.

By Comparison the popular Signal Link USB with Cable is $129.95 and has only 1 Radio Port and no GPS.

The best way to save Money is to do a group buy:

5% for 5 units 10% for 10. You can mix DRAWs and ThumbDV in the order.

Use coupons:

club5

club10




Re: Bring back the UDRC, alongside the DRAWS?

ve7fmn
 

Sorry for the false accusation Budd 😊
I was so taken by your helpful videos, really, that you name popped into my mind.
The cable was actually made by a ham who is listed as a resource in the UDRC-2 discussion. I followed the links and a cable showed up at my mail box. Too easy.
And thank you for taking time to make the you tube videos. Please make another showing how we can implement the onboard soundcard instead of a signalink or nomic (neither of which I have had roaring success with) with our KX3s to do those modes that use a soundcard to advantage.
Thank you again.
Fred VE7FMN

-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On Behalf Of Budd Churchward
Sent: Friday, December 7, 2018 8:47 PM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?

I have not made any cables. You probably got yours from Art Miller or Robert Sears. I think it is safe to assume that if the cable worked on your UDRC it is going to work on the DRAWS. Most of us are using standard cables with mini 6 pin DINs on both ends. Your radio doesn't have that connector so a cable had to be made for it. The mini 6 pin DIN is a pretty standard connector with the pins the same from radio to radio. If NWDR made a change to its connectors they would not be compatible with many radios. My DRAWS board came with two standard, off the shelf, cables. They are not doing anything special.

Budd Churchward
WB7FHC

-----Original Message-----
From: ve7fmn@...
Sent: Friday, December 07, 2018 8:36 PM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?

It’s the one Mr. Churchward made. I do not have a schematic. One end goes into the UDRC2 the other into a TRRS connector as used by KX3.


-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On
Behalf Of Bryan Hoyer
Sent: Friday, December 7, 2018 5:28 PM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?

Yes, the custom cable will work. You may have to change the alsamixer
settings to get the correct audio input as DRAWS has an analog mixer in the
front end to select Audio or Discriminator. Seeing as HF rigs don’t have
discriminator you need to set alsamixer ti IN_2 instead of the default IN_1
as on the UDRC.

Send me your cable spec and I’ll check it. I have a KX3 Online with DRAWS in
my shack.

Yes DRAWS can replace a SignalLink. Now I’m not bashing the SignalLink but
the transformer coupled audio prevents doing 9600 FSK on the High End and
4800 GMSK on the Loe end.

On Dec 7, 2018, at 9:03 AM, ve7fmn@... wrote:

OK, so then it begs the question, two actually...
I had a custom cable made to interface between the UDRC-2 and my KX3. Will
that cable work with my new to me DRAWS?
Can the DRAWS replace a signalink USB in additional to all of the other
cool things it does?
PS, mine arrived day before yesterday, thank you, and I was thoroughly
spanked by Canada customs and Canada Post (not thank you).


-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On
Behalf Of Bryan Hoyer
Sent: Friday, December 7, 2018 8:01 AM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?


Making 2 products causes inventory issues and makes both more expensive.

After we launched the ThumbDV we still get a couple of requests per year
for the PiDV but the economics don’t work out.

We spent a lot of time deciding on the GPS. With the UDRC one could add a
USB GPS but that wouldn’t give you PPS, which is arguably not a necessity
for Ham Radio but is pretty cool. DRAWS is also a 4 layer Board with
additional features; ADC, serial port, and Expansion connector, which
increases Ir’s cost.

We even did a survey and found that a majority of responders preferred the
on board GPS.

By Comparison the popular Signal Link USB with Cable is $129.95 and has
only 1 Radio Port and no GPS.

The best way to save Money is to do a group buy:

5% for 5 units 10% for 10. You can mix DRAWs and ThumbDV in the order.

Use coupons:

club5

club10




Re: Bring back the UDRC, alongside the DRAWS?

ve7fmn
 

It was W7TUT that made the cable.

-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On Behalf Of Budd Churchward
Sent: Friday, December 7, 2018 8:47 PM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?

I have not made any cables. You probably got yours from Art Miller or Robert Sears. I think it is safe to assume that if the cable worked on your UDRC it is going to work on the DRAWS. Most of us are using standard cables with mini 6 pin DINs on both ends. Your radio doesn't have that connector so a cable had to be made for it. The mini 6 pin DIN is a pretty standard connector with the pins the same from radio to radio. If NWDR made a change to its connectors they would not be compatible with many radios. My DRAWS board came with two standard, off the shelf, cables. They are not doing anything special.

Budd Churchward
WB7FHC

-----Original Message-----
From: ve7fmn@...
Sent: Friday, December 07, 2018 8:36 PM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?

It’s the one Mr. Churchward made. I do not have a schematic. One end goes into the UDRC2 the other into a TRRS connector as used by KX3.


-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On
Behalf Of Bryan Hoyer
Sent: Friday, December 7, 2018 5:28 PM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?

Yes, the custom cable will work. You may have to change the alsamixer
settings to get the correct audio input as DRAWS has an analog mixer in the
front end to select Audio or Discriminator. Seeing as HF rigs don’t have
discriminator you need to set alsamixer ti IN_2 instead of the default IN_1
as on the UDRC.

Send me your cable spec and I’ll check it. I have a KX3 Online with DRAWS in
my shack.

Yes DRAWS can replace a SignalLink. Now I’m not bashing the SignalLink but
the transformer coupled audio prevents doing 9600 FSK on the High End and
4800 GMSK on the Loe end.

On Dec 7, 2018, at 9:03 AM, ve7fmn@... wrote:

OK, so then it begs the question, two actually...
I had a custom cable made to interface between the UDRC-2 and my KX3. Will
that cable work with my new to me DRAWS?
Can the DRAWS replace a signalink USB in additional to all of the other
cool things it does?
PS, mine arrived day before yesterday, thank you, and I was thoroughly
spanked by Canada customs and Canada Post (not thank you).


-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On
Behalf Of Bryan Hoyer
Sent: Friday, December 7, 2018 8:01 AM
To: main@nw-digital-radio.groups.io
Subject: Re: [nw-digital-radio] Bring back the UDRC, alongside the DRAWS?


Making 2 products causes inventory issues and makes both more expensive.

After we launched the ThumbDV we still get a couple of requests per year
for the PiDV but the economics don’t work out.

We spent a lot of time deciding on the GPS. With the UDRC one could add a
USB GPS but that wouldn’t give you PPS, which is arguably not a necessity
for Ham Radio but is pretty cool. DRAWS is also a 4 layer Board with
additional features; ADC, serial port, and Expansion connector, which
increases Ir’s cost.

We even did a survey and found that a majority of responders preferred the
on board GPS.

By Comparison the popular Signal Link USB with Cable is $129.95 and has
only 1 Radio Port and no GPS.

The best way to save Money is to do a group buy:

5% for 5 units 10% for 10. You can mix DRAWs and ThumbDV in the order.

Use coupons:

club5

club10




Re: MMDVM & UDRC

Jonathan Naylor
 

Hi Annaliese

I've done the changes to use a 48 kHz sample rate with the MMDVM-UDRC. I'm making no guarantees but the values are based on the working 48 kHz branch of the main MMDVM firmware. The only area that bothers me is the output level for POCSAG which may be very out compared to the others.

This version should at least allow you to test with the UDRC and iron out any bugs.

I'd be very interested in any problems you find, and of course any pull requests that you may make to fix them. Remember that the DMR in this version is simplex only. Using the UDRC or similar hardware makes it impossible to have the type of synchronisation that duplex DMR repeating requires.

Jonathan  G4KLX


On Friday, 7 December 2018, 10:18:47 GMT, Annaliese McDermond <nh6z@...> wrote:
> On Dec 7, 2018, at 12:14 AM, Jonathan Naylor via Groups.Io <naylorjs=yahoo.com@groups.io> wrote:
>
> Hi Annaliese
>
> There are a set of filter coefficients for 48 kHz sample rate in a branch of the MMDVM firmware. I’ll look into slotting those in and altering the other variables.
>
> Ideally I’d recalculate them in MATLAB as floating point but my license for it ran out. Octave can probably do it though. Even rescaling from Q15 format will probably give enough precision.

If you have some matlab code, I have a Matlab 2015b license on my Mac that I could spit out the coefficients for you.  I’m mildly familiar with the process because I’ve done it for filter coefficients in the OpenHPSDR FPGA code that I was playing with.


> It’s bizarre seeing Linux kernel AX25 being mentioned. I wrote that stuff 23 years ago and last looked at it 20 years ago. I’m not sure I could add anything to that discussion these days.
>
> Jonathan G4KLX

--
Annaliese McDermond (NH6Z)
nh6z@...



Re: MMDVM & UDRC

Annaliese McDermond
 

Thanks Johnathan. I’ll be working a things a bit today and this evening.

On Dec 8, 2018, at 12:36 PM, Jonathan Naylor via Groups.Io <naylorjs=yahoo.com@groups.io> wrote:

Hi Annaliese

I've done the changes to use a 48 kHz sample rate with the MMDVM-UDRC. I'm making no guarantees but the values are based on the working 48 kHz branch of the main MMDVM firmware. The only area that bothers me is the output level for POCSAG which may be very out compared to the others.
I’ll mainly be concentrating on D-STAR, YSF and DMR since that’s what I have test gear for.

This version should at least allow you to test with the UDRC and iron out any bugs.

I'd be very interested in any problems you find, and of course any pull requests that you may make to fix them.
I have a serial code fix for the read side of things. The transplanted MMDVMHost code has different semantics than the code for MMDVM-UDRC expects. The MMDVMHost code blocks when it receives an initial chunk of data and then waits indefinitely until it reads the entire buffer length requested. This doesn’t work for MMDVM-UDRC because it blocks the main event thread waiting for more serial data that will never come.

I did some significant remodeling of the serial input code so that it reads a little bit more judiciously and uses the length field of the MMDVM frame to figure out how much to ask the OS to read for it. This seems to solve the problem. I’ll PR it soon so you can at least take a look at it.

Remember that the DMR in this version is simplex only. Using the UDRC or similar hardware makes it impossible to have the type of synchronisation that duplex DMR repeating requires.
I understand the synchronization issues surrounding the DMR time slots. I’d like to get the rest of the protocols working correctly and then Bryan and I have had recurring ideas on how we could potentially deal with that issue. I’m curious, though, how tight is the timing issue time-wise. Does the PTT have to cycle in 1ms, 10ms, 100ms? I’m assuming it’s the time from the preamble in that slot to when actual data begins to flow.

Jonathan G4KLX
--
Annaliese McDermond (NH6Z)
Xenotropic Systems
mcdermj@...




On Friday, 7 December 2018, 10:18:47 GMT, Annaliese McDermond <nh6z@...> wrote:
On Dec 7, 2018, at 12:14 AM, Jonathan Naylor via Groups.Io <naylorjs=yahoo.com@groups.io> wrote:

Hi Annaliese

There are a set of filter coefficients for 48 kHz sample rate in a branch of the MMDVM firmware. I’ll look into slotting those in and altering the other variables.

Ideally I’d recalculate them in MATLAB as floating point but my license for it ran out. Octave can probably do it though. Even rescaling from Q15 format will probably give enough precision.
If you have some matlab code, I have a Matlab 2015b license on my Mac that I could spit out the coefficients for you. I’m mildly familiar with the process because I’ve done it for filter coefficients in the OpenHPSDR FPGA code that I was playing with.


It’s bizarre seeing Linux kernel AX25 being mentioned. I wrote that stuff 23 years ago and last looked at it 20 years ago. I’m not sure I could add anything to that discussion these days.

Jonathan G4KLX
--
Annaliese McDermond (NH6Z)
nh6z@...



Re: Compass udrc kernel panic

f6bvp
 

To Jonathan Naylor via Groups.Io <naylorjs=yahoo.com@groups.io>

Hi Jonathan,

I contact you through nw-digital-radiogroups for the reason that we are
facing a kernel panic while using ROSE kernel module.
I am glad to see you are still involved in digital communications.
Of course, as you mentionned, it's been a while since you have been
involved in packet radio AX.25 development and peculiarly in the code we
are interested in here.

There is a part of the code causing kernel panic that I identified but I
don't really understand what is its purpose.

Here is the kernel panic context.

-------- Message transféré --------
Sujet : [ROSE] rose dereferenced pointer kernel panic
Date : Sat, 8 Dec 2018 16:17:02 +0100
De : f6bvp <f6bvp@...>
Pour : David Ranch <dranch@...>, Basil Gunn
<@basil860>, Ralf Bächle DL5RB <ralf@...>, Richard
Stearn <richard@...>
Copie à : C Schuman <k4gbb1@...>, linux-hams@...,
Annaliese McDermond <mcdermj@...>, Bernard Pidoux
<bernard.pidoux@...>

Hi All,

While running packet radio network switch ROSE node a kernel panic
occurs systematically when opening a Chromium session.

kernel is 4.14.79-v7+ on a Raspberry Pi with Compass Linux (Debian stretch).

According to Kernel message panic is related to ax25cmp() performed with
a null pointer argument.

The function from which ax25cmp() gets a NULL pointer is rose_route_frame().
Function rose_route_frame() is called by rose_xmit() in the following
code sequence with explicit NULL pointer argument :

if (!rose_route_frame(skb, NULL)) {
dev_kfree_skb(skb);
stats->tx_errors++;
return NETDEV_TX_OK;
}

In order to avoid fatal ax25cmp() comparison we could use the following
rose_route_frame patch that has been already proposed by a number of
observers facing such dereferenced pointer.

diff --git a/net/rose/rose_route.c b/net/rose/rose_route.c
index 452bbb38d943..8f2f1fb1707d 100644
--- a/net/rose/rose_route.c
+++ b/net/rose/rose_route.c
@@ -863,6 +863,10 @@ int rose_route_frame(struct sk_buff *skb, ax25_cb
*ax25)
int res = 0;
char buf[11];

+ if (ax25 == NULL) {
+ return res;
+ }
+
if (skb->len < ROSE_MIN_LEN)
return res;
frametype = skb->data[2];

I actually patched rose module kernel 4.14.79-v7+ on
my Raspberry Pi and it succeeded in preventing kernel panic.

However, this is not satisfactory as the code sequence calling
rose_route_frame with a NULL argument should certainly have been written
on purpose. My concern is that I don't understand the significance of
this code in case it would not trigger a kernel panic. Is this a bug ?
Instead of NULL argument, did the author want actually to send an empty
value ?

Richard Stearn explained formerly :
https://marc.info/?l=linux-hams&m=146866282201792&w=2
"Calling rose_route_frame with a NULL ax25 callback parameter indicates
a locally generated frame. The existing code does not handle the NULL
value and the kernel hard crashes in an interrupt, resulting in the
system stopping processing."

Francois Romieu in 2016 suggested to ask you what you meant when you
wrote rose_rebuild_header (since that's where Eric B. took rose_xmit
from) back in the 2.1.9 era ?
https://marc.info/?l=linux-netdev&m=145720784703135&w=2

I know this was written long time ago but I wonder if you could give me
some explanations about what the code is supposed to do and how we could
keep it and avoid kernel panic at the same time.

Regards,

Bernard Pidoux, f6bvp

locked DRAWS Questions

WA7SKG <wa7skg@...>
 

Sorry, I've been kind of slow keeping up with the DRAWS thing. From a quick scan, I see that it interfaces with two radios, has built in GPS and can do digital with any Linux software that will run on a RaspberryPi. So, I am guessing that includes fldigi for MT63/PSK31/etc. and Xastir for APRS and, hopefully something for SSTV.

My plan is to use this mobile on my RPi 3 B+ which is on a standard Pi Touch 7" touch screen. Right now, I have a TNC-Pi connected and a Y-cable that powers the RPi and the touchscreen. The RPi powers the TNC-Pi through the header. It looks like the DRAWS has a 12V input that powers the RPi. Will this also power the touchscreen? How precise must the 12V input be? Can it handle the variations of vehicle voltage, which could swing from 10-14 volts?

My mobile radios are an Icom IC-7100 and a Yaesu FT-8900. It looks like I should simply be able to plug generic 6-pin DIN cables between the DRAWS and the data ports on the radios.

Looking on the NW Digital web page, it looks like they are taking orders for the next run of DRAWS. I'd like to get a warm fuzzy my plans are viable so I can go ahead and place an order.

tnx es 73,
Michael WA7SKG

Re: Show US Your DRAW Photos

William Franzin
 

Hey folks. I went shopping for my kids tonight and found the perfect DRAWS Pi setup. 

Check out this kids toy! - which is on sale in Canada for $150 CAD for another 1h45 min at BestBuy.

It's a Pi3 kit with battery pack, 1280x800 LCD, wireless keyboard, USB hub etc. This is perfect. 


On Thu, Nov 29, 2018 at 12:30 AM Basil Gunn <basil@...> wrote:

I gave the wrong url for the Sunfounder displays that I've used.
These are the correct urls for the 7" & 10" LCD displays.

https://www.sunfounder.com/7-inch-hdmi-lcd.html
https://www.sunfounder.com/10-1-inch-hdmi-lcd.html

One more feature that I like is they run on 12V.
/Basil

Basil Gunn <basil@...> writes:

>> I just realized they made the same mistake on the DRAWS as they did on the UDRC series.
>
> Not really a mistake if you use the superior SunFounder 7" monitor
> (1024x600) which would have the HAT cables come out the top.
> https://www.amazon.com/SunFounder-Inch-Monitor-HDMI-Raspberry/dp/B073GYBS93/ref=sr_1_4
>
> I personally prefer the Sunfounder 10" display with 1280x800 resolution
> that allows enough screen real estate to run a mail client or
> Xastir. With the 10" screen the cables face the bottom but the RPi is
> mounted at the top of the display with plenty of room for the cables.
>
> The 7" & 10" Sunfounders come with a built in speaker, RPi mounting
> pieces & an HDMI cable to mate with the RPi. I believe (could be wrong)
> both sizes come with a touch screen option.
>
> The 800x400 Smart-Pi display was good for my console winlink apps, mutt
> with paclink-unix, but really didn't cut it for anything with a gui.
>
> /Basil
>
>
>> The mini-din connectors are on the same side as they were on the UDRC. This means if you try to use one on the "Smarti-Pi" cases with the touchscreen and hinged base the cables will be in the way just like they are with the UDRC.
>>
>> Oh well looks like I will have to remove the connectors like I did on the UDRC2
>
> Or just buy a better video screen.
>
> /Basil n7nix




Re: Compass udrc kernel panic

Jonathan Naylor
 

Hi Bernard


To be honest I remember very little about the ROSE implementation. It was over twenty years ago, and I haven't revisited since. I'm pretty sure I handed over maintenance to someone else. As such I can't really help you, I've moved on to other projects which take all my time and I don't feel minded to dig into such old code. Surely it's more of a case that the software calling it should be modified to not do so, or maybe someone else would like to have a look.

I'm sorry to be evasive, but my input is about as useful as someone else's after this amount of time.

Jonathan  G4KLX


On Saturday, 8 December 2018, 23:33:08 GMT, f6bvp <f6bvp@...> wrote:


To Jonathan Naylor via Groups.Io <naylorjs=yahoo.com@groups.io>

Hi Jonathan,

I contact you through nw-digital-radiogroups for the reason that we are
facing a kernel panic while using ROSE kernel module.
I am glad to see you are still involved in digital communications.
Of course, as you mentionned, it's been a while since you have been
involved in packet radio AX.25 development and peculiarly in the code we
are interested in here.

There is a part of the code causing kernel panic that I identified but I
don't really understand what is its purpose.

Here is the kernel panic context.

-------- Message transféré --------
Sujet : [ROSE] rose dereferenced pointer kernel panic
Date : Sat, 8 Dec 2018 16:17:02 +0100
De : f6bvp <f6bvp@...>
Pour : David Ranch <dranch@...>, Basil Gunn
<basil@...>, Ralf Bächle DL5RB <ralf@...>, Richard
Stearn <richard@...>
Copie à : C Schuman <k4gbb1@...>, linux-hams@...,
Annaliese McDermond <mcdermj@...>, Bernard Pidoux
<bernard.pidoux@...>

Hi All,

While running packet radio network switch ROSE node a kernel panic
occurs systematically when opening a Chromium session.

kernel is 4.14.79-v7+ on a Raspberry Pi with Compass Linux (Debian stretch).

According to Kernel message panic is related to ax25cmp() performed with
a null pointer argument.

The function from which ax25cmp() gets a NULL pointer is rose_route_frame().
Function rose_route_frame() is called by rose_xmit() in the following
code sequence with explicit NULL pointer argument :

        if (!rose_route_frame(skb, NULL)) {
                dev_kfree_skb(skb);
                stats->tx_errors++;
                return NETDEV_TX_OK;
        }

In order to avoid fatal ax25cmp() comparison we could use the following
rose_route_frame patch that has been already proposed by a number of
observers facing such dereferenced pointer.

diff --git a/net/rose/rose_route.c b/net/rose/rose_route.c
index 452bbb38d943..8f2f1fb1707d 100644
--- a/net/rose/rose_route.c
+++ b/net/rose/rose_route.c
@@ -863,6 +863,10 @@ int rose_route_frame(struct sk_buff *skb, ax25_cb
*ax25)
    int res = 0;
    char buf[11];

+    if (ax25 == NULL) {
+        return res;
+    }
+
    if (skb->len < ROSE_MIN_LEN)
        return res;
    frametype = skb->data[2];

I actually patched rose module kernel 4.14.79-v7+ on
my Raspberry Pi and it succeeded in preventing kernel panic.

However, this is not satisfactory as the code sequence calling
rose_route_frame with a NULL argument should certainly have been written
on purpose. My concern is that I don't understand the significance of
this code in case it would not trigger a kernel panic. Is this a bug ?
Instead of NULL argument, did the author want actually to send an empty
value ?

Richard Stearn explained formerly :
https://marc.info/?l=linux-hams&m=146866282201792&w=2
"Calling rose_route_frame with a NULL ax25 callback parameter indicates
a locally generated frame.  The existing code does not handle the NULL
value and the kernel hard crashes in an interrupt, resulting in the
system stopping processing."

Francois Romieu in 2016 suggested to ask you what you meant when you
wrote rose_rebuild_header (since that's where Eric B. took rose_xmit
from) back in the 2.1.9 era ?
https://marc.info/?l=linux-netdev&m=145720784703135&w=2

I know this was written long time ago but I wonder if you could give me
some explanations about what the code is supposed to do and how we could
keep it and avoid kernel panic at the same time.

Regards,

Bernard Pidoux, f6bvp


locked Re: DRAWS Questions

Jack Spitznagel
 

Michael,

I will be interested to hear the NWD response to your question about fluctuations in power/mobile usage. The 12V line will not feed the display, you will need a separate 5V supply.

Experimenting now with a DRAWS, RPi 3B+, plus Raspberry 7" touch display mounted in a "SmartiPi Touch" display stand. This is all powered through the 5V "Y" microUSB adapter. I am using the stock 2.5A wall wart that Pi foundation supplies in their kits (probably groaning under load). I plan to change over to a higher capacity USB multiline charger when I find what I want. YMMV but this works for me.

KD4IZ
Jack Spitznagel
FM19oo

-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On Behalf Of WA7SKG via Groups.Io
Sent: Saturday, December 8, 2018 09:13
To: main@nw-digital-radio.groups.io
Subject: [nw-digital-radio] DRAWS Questions

Sorry, I've been kind of slow keeping up with the DRAWS thing. From a quick scan, I see that it interfaces with two radios, has built in GPS and can do digital with any Linux software that will run on a RaspberryPi. So, I am guessing that includes fldigi for MT63/PSK31/etc.
and Xastir for APRS and, hopefully something for SSTV.

My plan is to use this mobile on my RPi 3 B+ which is on a standard Pi Touch 7" touch screen. Right now, I have a TNC-Pi connected and a Y-cable that powers the RPi and the touchscreen. The RPi powers the TNC-Pi through the header. It looks like the DRAWS has a 12V input that powers the RPi. Will this also power the touchscreen? How precise must the 12V input be? Can it handle the variations of vehicle voltage, which could swing from 10-14 volts?

My mobile radios are an Icom IC-7100 and a Yaesu FT-8900. It looks like I should simply be able to plug generic 6-pin DIN cables between the DRAWS and the data ports on the radios.

Looking on the NW Digital web page, it looks like they are taking orders for the next run of DRAWS. I'd like to get a warm fuzzy my plans are viable so I can go ahead and place an order.

tnx es 73,
Michael WA7SKG

Re: Show US Your DRAW Photos

Budd Churchward
 

Looking at the photo of the case from the rear, you can see that the Rpi header is occupied by a board with a connector coming from it. That is where you need to install the DRAWS board.
 

Sent: Saturday, December 08, 2018 10:18 PM
Subject: Re: [nw-digital-radio] Show US Your DRAW Photos
 
Hey folks. I went shopping for my kids tonight and found the perfect DRAWS Pi setup. 
 
Check out this kids toy! - which is on sale in Canada for $150 CAD for another 1h45 min at BestBuy.
 
It's a Pi3 kit with battery pack, 1280x800 LCD, wireless keyboard, USB hub etc. This is perfect.
 
 
On Thu, Nov 29, 2018 at 12:30 AM Basil Gunn <basil@...> wrote:

I gave the wrong url for the Sunfounder displays that I've used.
These are the correct urls for the 7" & 10" LCD displays.

https://www.sunfounder.com/7-inch-hdmi-lcd.html
https://www.sunfounder.com/10-1-inch-hdmi-lcd.html

One more feature that I like is they run on 12V.
/Basil

Basil Gunn <basil@...> writes:

>> I just realized they made the same mistake on the DRAWS as they did on the UDRC series.
>
> Not really a mistake if you use the superior SunFounder 7" monitor
> (1024x600) which would have the HAT cables come out the top.
> https://www.amazon.com/SunFounder-Inch-Monitor-HDMI-Raspberry/dp/B073GYBS93/ref=sr_1_4
>
> I personally prefer the Sunfounder 10" display with 1280x800 resolution
> that allows enough screen real estate to run a mail client or
> Xastir. With the 10" screen the cables face the bottom but the RPi is
> mounted at the top of the display with plenty of room for the cables.
>
> The 7" & 10" Sunfounders come with a built in speaker, RPi mounting
> pieces & an HDMI cable to mate with the RPi. I believe (could be wrong)
> both sizes come with a touch screen option.
>
> The 800x400 Smart-Pi display was good for my console winlink apps, mutt
> with paclink-unix, but really didn't cut it for anything with a gui.
>
> /Basil
>
>
>> The mini-din connectors are on the same side as they were on the UDRC. This means if you try to use one on the "Smarti-Pi" cases with the touchscreen and hinged base the cables will be in the way just like they are with the UDRC.
>>
>> Oh well looks like I will have to remove the connectors like I did on the UDRC2
>
> Or just buy a better video screen.
>
> /Basil n7nix




Re: Show US Your DRAW Photos

William Franzin
 

Correct. The stock power button is a pi hat connected to the usb battery pack. 

Based on the angle that also means the draws board should fit easily inside. I'm going to use a laser cutter on the side to cut holes for the mini din connectors. 

For power it appears the 2x18650 pack is configured something like a ups. For a home setup I think this will work well with just a little mod work. 

There's also enough room for the AMBE stick which I'll be using for transcoding. I'm working on voice control projects and will be using draws for digital voice. 

This is what I've been up to:


On Sun, Dec 9, 2018, 11:23 AM Budd Churchward <budd@... wrote:
Looking at the photo of the case from the rear, you can see that the Rpi header is occupied by a board with a connector coming from it. That is where you need to install the DRAWS board.
 
Sent: Saturday, December 08, 2018 10:18 PM
Subject: Re: [nw-digital-radio] Show US Your DRAW Photos
 
Hey folks. I went shopping for my kids tonight and found the perfect DRAWS Pi setup. 
 
Check out this kids toy! - which is on sale in Canada for $150 CAD for another 1h45 min at BestBuy.
 
It's a Pi3 kit with battery pack, 1280x800 LCD, wireless keyboard, USB hub etc. This is perfect.
 
 
On Thu, Nov 29, 2018 at 12:30 AM Basil Gunn <basil@...> wrote:

I gave the wrong url for the Sunfounder displays that I've used.
These are the correct urls for the 7" & 10" LCD displays.

https://www.sunfounder.com/7-inch-hdmi-lcd.html
https://www.sunfounder.com/10-1-inch-hdmi-lcd.html

One more feature that I like is they run on 12V.
/Basil

Basil Gunn <basil@...> writes:

>> I just realized they made the same mistake on the DRAWS as they did on the UDRC series.
>
> Not really a mistake if you use the superior SunFounder 7" monitor
> (1024x600) which would have the HAT cables come out the top.
> https://www.amazon.com/SunFounder-Inch-Monitor-HDMI-Raspberry/dp/B073GYBS93/ref=sr_1_4
>
> I personally prefer the Sunfounder 10" display with 1280x800 resolution
> that allows enough screen real estate to run a mail client or
> Xastir. With the 10" screen the cables face the bottom but the RPi is
> mounted at the top of the display with plenty of room for the cables.
>
> The 7" & 10" Sunfounders come with a built in speaker, RPi mounting
> pieces & an HDMI cable to mate with the RPi. I believe (could be wrong)
> both sizes come with a touch screen option.
>
> The 800x400 Smart-Pi display was good for my console winlink apps, mutt
> with paclink-unix, but really didn't cut it for anything with a gui.
>
> /Basil
>
>
>> The mini-din connectors are on the same side as they were on the UDRC. This means if you try to use one on the "Smarti-Pi" cases with the touchscreen and hinged base the cables will be in the way just like they are with the UDRC.
>>
>> Oh well looks like I will have to remove the connectors like I did on the UDRC2
>
> Or just buy a better video screen.
>
> /Basil n7nix




locked Re: DRAWS Questions

WA7SKG <wa7skg@...>
 

Jack,
How does the DRAWS work with the SmartiPi case? I saw some comments that there may be issues with the cables interfering with the stand. Not really a problem since I do not use the stand, I have mine on a VESA mount for mobile use. The DIN connectors should be okay, but the other connectors may be an issue. The pictures show two connectors on the left side. I guess one is for power, but I don't know what the other one is for.

I guess I'll need to run the RPi/DRAWS from the 12V lines and the touch screen from the 5V supply.

I do need to see the NWD response however on the 12V variations before I spend money on it.

73,
Michael WA7SKG


Jack Spitznagel wrote on 12/9/18 06:47:

Michael,
I will be interested to hear the NWD response to your question about fluctuations in power/mobile usage. The 12V line will not feed the display, you will need a separate 5V supply.
Experimenting now with a DRAWS, RPi 3B+, plus Raspberry 7" touch display mounted in a "SmartiPi Touch" display stand. This is all powered through the 5V "Y" microUSB adapter. I am using the stock 2.5A wall wart that Pi foundation supplies in their kits (probably groaning under load). I plan to change over to a higher capacity USB multiline charger when I find what I want. YMMV but this works for me.
KD4IZ
Jack Spitznagel
FM19oo
-----Original Message-----
From: main@nw-digital-radio.groups.io <main@nw-digital-radio.groups.io> On Behalf Of WA7SKG via Groups.Io
Sent: Saturday, December 8, 2018 09:13
To: main@nw-digital-radio.groups.io
Subject: [nw-digital-radio] DRAWS Questions
Sorry, I've been kind of slow keeping up with the DRAWS thing. From a quick scan, I see that it interfaces with two radios, has built in GPS and can do digital with any Linux software that will run on a RaspberryPi. So, I am guessing that includes fldigi for MT63/PSK31/etc.
and Xastir for APRS and, hopefully something for SSTV.
My plan is to use this mobile on my RPi 3 B+ which is on a standard Pi Touch 7" touch screen. Right now, I have a TNC-Pi connected and a Y-cable that powers the RPi and the touchscreen. The RPi powers the TNC-Pi through the header. It looks like the DRAWS has a 12V input that powers the RPi. Will this also power the touchscreen? How precise must the 12V input be? Can it handle the variations of vehicle voltage, which could swing from 10-14 volts?
My mobile radios are an Icom IC-7100 and a Yaesu FT-8900. It looks like I should simply be able to plug generic 6-pin DIN cables between the DRAWS and the data ports on the radios.
Looking on the NW Digital web page, it looks like they are taking orders for the next run of DRAWS. I'd like to get a warm fuzzy my plans are viable so I can go ahead and place an order.
tnx es 73,
Michael WA7SKG

locked Re: DRAWS Questions

 

Please follow this topic on the UDRC subgroup -- https://nw-digital-radio.groups.io/g/udrc/message/2148

locked Ras Pi3 B+ #draws

Robert KF6FOD
 

does it matter if you use a Pi 3B or B+ with the draws hat?