On Sat, 19 May 2018 13:39:39 +0000 (UTC), Martin Gregorie wrote:

>> As the AXE027 is designed for a PICAXE is it using TTL 0 - 5 V
signal
>> levels or proper RS232 +/- 12 V? What does the KRT2 expect?
>
> Good point and one I didn't think of but should have - I'm too used to
> stuff that works on either TTL or 12v.

And some times devices aren't too fussy and work anyway...

> The manuals I have include one for the presets up/download connection,
> but that expects the PC to have an RS-232 serial port and, again,
> doesn't mention the expected signal level.

I'd expect a PC RS232 port to be +/- 12 V.

>> Can you monitor the Tx and Rx an lines and see if data is being
sent on
>> either.

> Thats difficult logistically, but I think I can get a scope on the
> lines, which may be easier than powering a logic probe or adding LEDs.

And will give you a definative on the levels, that LEDs or logic
probe wouldn't.

> USB-serial adapters are obviously running off 5v, but do they normally
> provide 12v or TTL levels on their RS232 pins?

Ones proporting to be "RS232" rather than just "serial" ought to
provide +/- 12 V.

--
Cheers
Dave.

--- SoupGate-Win32 v1.05