How are CW keystrokes transported from the Maestro to the FlexRadio ?

Bill Bailey

I am interested in constructing a WIFI/RasberryPI CW paddle keyer. I can not find any information in the API description that describes the CW data flow from the Maestro to the Flex.

Has anyone considered doing this ?

Best Regards,

Bill Bailey

KD0RC

Hi Bill, IW7DMH has done this as well as RemoteKeyerInterface on Groups.io. Check both of these websites for more info on how they are accomplishing it. I am currently experimenting with the IW7DMH code, but I just got started on it this morning (thanks for the motivation @Mike-VA3MW !). As I get more into the inner workings, I will post back here with my progress.

So far I have the listening side ported to a Teensy 4.1 (PJRC.com). It compiles and runs, but can't yet tell if it is actually working. This afternoon, I will see if I can communicate with it using the internal keyer in my TeensyMaestro.

I don't know how the Maestro does it, but the people doing it now seem to use a dedicated board like an Arduino or Raspberry PI to physically key the Flex using the key jack or accessory jack. This is the approach I am taking with the IW7DMH code that I ported over from the Arduino platform.

Martin AA6E

I've wondered about this, too. It seems like a difficult problem if you want QRQ (fast) sending over a flakey wifi/internet connection. I suppose the Maestro could send a key down or up UDP packet. But then a dropped packet could latch up the Tx. Etc.

Someone should measure timing jitter from key down to RF out just for fun while working remote.

Bill Bailey

Multiple samples per dot or dash might cure your latching problem. Multiple samples makes it a level detection scheme rather than an edge scheme. Just supposing.... I am hoping that the Flex Help desk guys can shed some light on this.

B.B.....

KD0RC

One thought I had is to send 8 bit WPM followed by 1 for dot or 3 for dash. This two byte packet would not leave it in xmit, even with dropped packets. This would only work for keyer or keyboard generated code. For hand keying, a start and stop code with a 100 ms time out might work. Tricky business, this!

Bill Bailey

Flex has solved this problem, I am hoping they will share the technique..