Regular Member
Joined: 27/09/2011
Location: AustraliaPosts: 55
| Posted: 11:11am 01 Oct 2018 |
@Azure, I have one dil chip in a breadboard, and one SOIC chip on one of Mick's serial backpack boards. In each case, nothing else connected, external power, 10uf ceramic on pin 20, and check the ctrl C signal with a couple of different scopes.
At the moment I get no response at all with any of the Win 7 adapters, while the Microbridge and a Win 10 machine work normally.
At 38.4 kb, Ctrl C produces (consistently), a 25usec negative pulse, followed 50usecs later by 160usec pulse. This normally results in a burst of characters from the console Tx pin, and the arrow prompt in MMedit chat window. Communication and loading will then work.
Not so if otherwise. If the above is the correct pulse waveform, why will a fresh chip not respond?
Or are my pulses different from everyone elses? Hmmm...