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by Lomax
Mon Feb 03, 2020 1:07 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Is it this character? character3.jpg Thank you, that's seems likely - it even follows some other currency symbols in the table. Also explains why I thought it looked familiar, and why I was unable to find it in the Unicode space (in virtually every case it is shown as "Pts", not "Pt"). But since Sp...
by Lomax
Sun Feb 02, 2020 11:18 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Decoding the extended characters confirmed they were sequential, with an offset of 32 (decimal), so the full list of extended characters can be translated like this : def extended(s): chars = ["Ç","ü","é","â","ä","à","å","ç","ê","ë","è","ï","î","ì","Ä","Å","É","æ","Æ","ô","ö","ò","û","ù","ÿ","Ö","Ü"...
by Lomax
Sun Feb 02, 2020 4:35 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Or, even better, create a dictionary ... extended = { } extended[ "å" ] = chr(0x08)+chr(0x26) extended[ "ä" ] = chr(0x08)+chr(0x24) extended[ "ö" ] = chr(0x08)+chr(0x34) etc for key in extended: s = s.replace(key, extended[key]) Great, many thanks! My version: def extended(s): chartbl = {"å": 0x26,...
by Lomax
Sun Feb 02, 2020 2:14 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

One small problem remains; I need to send some extended ASCII characters, such as "åäö". This works in the InView software, but I don't understand how they're encoded. If I send them raw the display shows "C%C$C6", and if I monitor what the InView app sends it looks like this: txt: å ä ö raw: C% C$ ...
by Lomax
Sun Feb 02, 2020 4:57 am
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Bingo. I think you're in the home stretch. Indeed! It's been an interesting battle - and one I could not have won without your kind help. Many thanks! After a bit more trial & error, careful re-reading of the manual, and comparing the strings my code generates with what's sent by the InView app, I'...
by Lomax
Sat Feb 01, 2020 3:25 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Using Serial Port Monitor I've been able to capture this output, when setting message #001 to "Hello": :01010064.Z01.A0001.0b..0.3.1Hello... 3a 30 31 30 31 30 30 36 34 01 5a 30 31 02 41 30 30 30 31 1b 30 62 16 1e 30 1a 33 1c 31 48 65 6c 6c 6f 04 0d 0a The string is a little different, using full sto...
by Lomax
Sat Feb 01, 2020 2:24 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Stop the press - there's been a break through! testing_testing.jpg I spent some more time digging around for the official software, and after finding a list of version numbers I had success with a search for "InView 2.6" - which was available to download from Software Informer . Installing it in a W...
by Lomax
Fri Jan 31, 2020 4:41 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

This seems to work for me, Python 2 ... Thanks muchly! I tried a few things such as: #!/usr/bin/env python3 # encoding: utf-8 from time import sleep import serial, base64 display = serial.Serial("/dev/ttyUSB1", 9600, 7, serial.PARITY_EVEN, 2) def Hex(n,w): s = hex(n)[2:].upper() if len(s) < w : s =...
by Lomax
Fri Jan 31, 2020 11:29 am
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

This sends the ASCII payload "^AZ00^BA2001 Hello^D" I am not sure it does. That looks more like an incrementing set of 16-bit values as 4-digit hex to me. May be a bug / diagnostics in your message forming code. I'd be expecting ": ... 5E415A30305E4241323030312048656C6C6F5E44 ... \r\n", where you w...
by Lomax
Wed Jan 29, 2020 10:26 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

I would assume ... : = start of message 01 = dunno 06 = your 6 00 = your 0 66 = your 102 007B = your 123 18 = checksum \r\n = CR-LF I am deeply impressed - you are indeed correct! The "dunno" is the unit's Modbus address. The following 06 is the function code, 00 high register address, 66 low regis...
by Lomax
Wed Jan 29, 2020 9:06 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Some further progress, I can now clear the message cue (I think), and tell it to display a specific message #: initialised.png #!/usr/bin/env python3 # encoding: utf-8 from time import sleep import minimalmodbus display = minimalmodbus.Instrument("/dev/ttyUSB1", 1, minimalmodbus.MODE_ASCII, debug=Tr...
by Lomax
Wed Jan 29, 2020 12:51 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Some progress:

Code: Select all

#!/usr/bin/env python3
# encoding: utf-8

import minimalmodbus

display = minimalmodbus.Instrument("/dev/ttyUSB1", 1, minimalmodbus.MODE_ASCII)
display.serial.baudrate = 9600
print(display.read_registers(1,2))


Gives the response:

Code: Select all

[0, 0]


Which is the expected result.
by Lomax
Wed Jan 29, 2020 10:45 am
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

see http://www.simplymodbus.ca/ASCII.htm Ah, thank you, that clears things up. So in short, Modbus ASCII is always 7 bit, and has a parity bit: In Modbus RTU each byte is sent as a string of 8 binary characters framed with a start bit, and a stop bit, making each byte 10 bits. In Modbus ASCII, the ...
by Lomax
Tue Jan 28, 2020 8:18 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Unfortunately I know nothing of modbus. I don't know if 9600 would be the appropriate baud rates but I would have thought 8 data bits ( display.serial.bytesize = 8 ) might be worth trying and I would start with a simpler message; msg = "TEST^D" I've used Modbus a few times, but find the manual for ...
by Lomax
Tue Jan 28, 2020 2:23 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

The protocol seemed simple enough to me though I haven't studied it all in depth. As far as I can see you need to download messages and then tell the displays which messages to show. Seems to me you can clear the display's memory, download one message, tell it to display it, then simply download a ...
by Lomax
Sat Jan 25, 2020 2:03 pm
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Re: Looking for 2x20 LED matrix display

Thank you, that's a pretty good option - but the display modules used are a bit big; one of the reasons I bought the "InView" displays is that they use 0.7" tall modules, which is perfect for my application. 1.25" tall modules will be too large :( Anyone know of a similar product which uses 0.7" or ...
by Lomax
Fri Jan 24, 2020 10:07 am
Forum: General discussion
Topic: Looking for 2x20 LED matrix display
Replies: 28
Views: 3173

Looking for 2x20 LED matrix display

Hi all, I need to find a 2x20 character LED matrix display to display simple text messages (monochrome, bicolour or full colour does not matter) with a ~1" character height. I bought a couple of second hand Rockwell Automation 2706-P22R for cheap on the bay (also sold under the "Allen-Bradley" and "...
by Lomax
Sat Oct 05, 2019 9:30 pm
Forum: Interfacing (DSI, CSI, I2C, etc.)
Topic: HDMI to CSI2 (TC358743) Raspbian Buster
Replies: 2
Views: 2372

Re: HDMI to CSI2 (TC358743) Raspbian Buster

uv4l is a closed source project, so you need RpiName or others involved in linux-projects.org to update things. Some people have reported that the Stretch packages will just work with some jiggery-pokery. I'm curious about this - I only recently started looking at uv4l and immediately got a bad vib...
by Lomax
Tue Sep 10, 2019 1:02 pm
Forum: General discussion
Topic: Still confused, what is better for my SD card?
Replies: 19
Views: 1660

Re: Still confused, what is better for my SD card?

You don't want to do more writes than necessary! Just leave the controller alone doing wear leveling for you. There is a rule of thumb to leave at least 10% of the capacity free to avoid slowdowns and early failure. If you need more space it's time for an upgrade. Thanks, I'll go with 6Gb partition...
by Lomax
Tue Sep 10, 2019 10:26 am
Forum: General discussion
Topic: Still confused, what is better for my SD card?
Replies: 19
Views: 1660

Re: Still confused, what is better for my SD card?

well it depends on the controller on the card it may or may not work... the only way you can help is not by writing it so it's nearly full all the time I usually use these cards when I need high reliability: Sandisk Industrial MicroSD.jpg Not terribly expensive, IIRC ~£10 each when bought in quanti...
by Lomax
Tue Sep 10, 2019 9:49 am
Forum: General discussion
Topic: Still confused, what is better for my SD card?
Replies: 19
Views: 1660

Re: Still confused, what is better for my SD card?

just because you have defined partitions for yourself, which are just ranges of block numbers, does not mean the SD card won't use whatever actual physical space it likes. I've read this sentence several times but still not sure if that's a "yes, leaving unpartitioned space helps with wear levellin...
by Lomax
Tue Sep 10, 2019 8:57 am
Forum: General discussion
Topic: Still confused, what is better for my SD card?
Replies: 19
Views: 1660

Re: Still confused, what is better for my SD card?

Re. wear levelling, if I only need a fraction of the space on a given card, is it better to leave some space unpartitioned, or should my partitions take up 100% of what's available? Maybe it makes no difference?
by Lomax
Mon May 06, 2019 11:23 am
Forum: Graphics, sound and multimedia
Topic: Oculus Rift CV1 compatibility
Replies: 7
Views: 985

Re: Oculus Rift CV1 compatibility

I'll have to give up on using a Pi for this. I'm guessing an Odroid C2 would be able to provide the required bandwidth? It does HDMI 2.0 [email protected] Hz. We're only going to use the Rift for stereoscopic 360° video playback, so 3D performance is pretty irrelevant. Edit: I've now ordered an MSI "Cubi N" min...
by Lomax
Sun May 05, 2019 9:26 pm
Forum: Graphics, sound and multimedia
Topic: Oculus Rift CV1 compatibility
Replies: 7
Views: 985

Re: Oculus Rift CV1 compatibility

Another update: Just to verify the basic approach to getting the Rift to work at all on Linux (i.e. using OpenHMD) I did a quick test with a Devuan live USB stick on a spare laptop. Sure enough, after downloading and building OpenHMD (and dependencies), the "simple" example they provide fired up the...
by Lomax
Sun May 05, 2019 7:42 pm
Forum: Graphics, sound and multimedia
Topic: Oculus Rift CV1 compatibility
Replies: 7
Views: 985

Re: Oculus Rift CV1 compatibility

Some further developments. I figured I'd try with some common display mode that the Rift might support and set /boot/config.txt to hdmi_drive=2 hdmi_force_hotplug=1 hdmi_group=1 hdmi_mode=16 which should mean [email protected]. But while I do get a response from the Rift with this setting (the LED turns wh...

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