[HECnet] SC-40

[Johnny Billquist]

On 2015-02-12 18:17, Cory Smelosky wrote:
Check later on, I tried every one my 420 offers...not all shown in video
though

Jeez. Ok, looked through the whole video.

You need to calm down and stop being all over the place.

First of all, since some characters work, while others do not, it's extremely likely that it's a problem with your serial comm setup.

Stop hitting all kind of random keys that you do not know what they do, it do not help. For your information, the arrow keys, as well as the "DO" key, and others, all send several characters over the serial line. Do not use them for now. Not only will it just confuse you, if the system don't actually understand such sequences as these keys send, you might get very strange and unwanted effects on the SC40.

Second, try to understand what you actually do when you change different things in the VT420.

Latin-1 vs. DEC MCS for instance, is totally irrelevant here.

Serial communication is not really that hard, but the way you just change things around suggest that you don't understand it.
Start with just 7 bits no parity. Try both one and two stop bits. Then move on from there.

Bob also suggested that you might have mixed up GND and TX, which actually is a good suggestion.
CR is 015(8), while } is 175(8). In fact, all those } suggests that 1 and 0 could be mixed up, in which case you also fail on the start bit, in addition to getting all those ones...

I would probably try just looping back TX to RX at the SC40 end of the cable to verify that the cable is correct. That would reveal if you did this mistake...

	Johnny

	Johnny


Sent from my iPhone

On Feb 12, 2015, at 12:15, Jim Carpenter <jim at deitygraveyard.com
<mailto:jim at deitygraveyard.com>> wrote:


On Feb 12, 2015 12:11 PM, "Cory Smelosky" <b4 at gewt.net
<mailto:b4 at gewt.net>> wrote:
> https://www.youtube.com/watch?v=2LAPAwzoeiQ
>
> Here's a video of what it does.
>
>

Typing some letters works but others don't? Check your parity.

Jim