On Sun, 12 Feb 2012 11:28:00 Dan Smith wrote:
I will try another 4-pin cable. And I will try a diode between Tx and Rx. It seems to me that the radio is trying to pull down the data line, but the PC Tx line is pulling up (idle).
None of the radios I've built cables for (which is many) have ever had a diode in the mix. The radio expects to see its own echo, so if you try to prevent that with the diode, then it will stop transferring immediately. If you put the diode the other way, then you haven't changed the circuit any.
I'm still not sure. The radio will always see its own data, as Tx and Rx are connected internally. If I use a diode then it stops the idle state of PC Tx fighting (pulling up) if the radio wants to pull it down.
I have added a diode and I have made some progress. VX2 Commander 'sees' the radio, but only gets one block of data. It seems the protocol is block oriented- radio sends some data and waits for something before proceeding.
Here's the dump from VX2 Commander: Data Received. Length: 11 Data: 41 48 30 31 35 24 E8 01 00 24 00 First Block: [41 48 30 31 35 24 E8 01 00 24] ------------------------------------- CPU: 01 00 USA Mod Setting: E8 (Freeband) ------------------------------------- Sent: 06 Acknowledge...
Then the radio times out and displays "ERROR".
Next, I can see data using gtkterm running at 19.2k 8 data bits, no parity. I get "AH015" !
So, with Chirp I get this trace: CHIRP 0.1.12 on Linux - MEPIS Linux 8.0 Clone thread started 000: 41 48 30 31 35 24 e8 01 AH015$.. 008: 00 24 00 00 00 00 00 00 .$......
Then the radio times out and I have to hit Cancel.
I have some chores to get on with, but I'll keep trying different things when I have time.
73,
Andrew ZL3AME