My Adventures Building HAMLib support for the OpenRadio SDR board

About me

Paul Warren

@pawarren

VK1ATP

Sysadmin for Money, Coding for fun!

These slides available at: https://github.com/pwarren/OpenRadio2017

The OpenRadio SDR Board

The OpenRadio SDR Board

• Inexpensive SDR Receiver + PSK31 Transmitter
• Constructed at the Auckland LCA in 2015
• HF (~0->30MHz)
• Tayloe Detector type SDR
• Arduino control system
• Outputs to a Soundcard
• Works well at 48kHz sampling rate
• Kits no longer sold 😢
• Schematics/Gerbers available at: (Harrass Mark VK5QI)
• Various firmware already made

My favourite SDR software

CubicSDR.com

Getting them to talk!

Enter HAMlib

An easy to use library to interface with various radios

Abstracts out serial protocols

Testing tool comes with the package

rigctl -m 228 -r /dev/ttyUSB0 -s 9600 F 7090000

How hard can it be?

I know, I have an FT-817, I'll emulate that!

Got a bit of the way through

5 byte blocks

4 param bytes, one command byte
{0x00,0x70,0x90,0x00,0x01} tunes to 7 090 000 Hz

ergh: convert integer's to BCD

Some _days_ attempting to get BCD encoding/decoding to work

Sanity Prevails!

Thanks to VK5ZM

TS-430 protocol is much easier

37 chars
P1: 11 digits freqency in Hz
P2: 5 spaces
P3: 5 digit RIT Freq
P4: 1 digit RIT Status
P5: 1 digit XIT Status
P6: 0

P7: 2 digit Mem channel (00-99)
P8: 1 digit TX status
P9: 1 char Operating Mode
P10: 1 char FT/FR
P11: 1 char Scan Status
P12: 1 digit Simplex Status
P13: 1 digit OFF/Tone/CTCSS
P14: 2 digit Tone Number
P15: 1 space
TRM: ;

Sanity Prevails!

Character based

No more binary packing

No More BCD encoding/decoding!

Responses have variable length but terminations are easy: ';'

finished in a few hours

Code available at: https://github.com/darksidelemm/open_radio_miniconf_2015/tree/master/openradio_cat

And here it is working!

Live Demo

Next Steps?

I don't know!

PSK TX capabilities not easily done with ts-480 spec

Will have to come up with a another protocol

Implement in Arduino and C

It does what I want

Questions?

Bonus Content