forums.nabu.ca

Hello,

Wife just got me a NABU personal computer for Christmas as I had been talking about it for months. I am fascinated by this technology as it was way ahead of it's time. Hoping to get it online soon but a little confused about what came with the unit from the seller.

My NABU came with short cable consisting of a 5-pin DIN to a TTL 5V to RS422 serial converter mini board with outputs of VCC, GRN, RXD, and TXD but the NABU onboard UA9637AC is already RS422? Looking to best understand how this would be connected to a USB serial emulator as all other videos I've seen have different pin outs and just use the DTech USB to RS422 Serial Port Converter connected directly to a 5 pin DIN without this TTL 5V to RS422 serial converter. So I just bought the adapter from Amazon, though I would like to still utilize what came with the system if possible though it seems to be redundant.

Derek

Question answered by:

"by DJ Sures » Sat Dec 16, 2023 10:34 am
The only way you could use that is if you bought additional hardware. You’d need to purchase a uart to usb adapter for that. I’m not sure who you bought it from but hopefully they didn’t try charging you for that adapter "

You need a Serial USB to 5V TTL adaptor as mentioned above. What you have there is a TTL single ended RX/TX to RS422 differential RX/TX.

Yes the NABU has a RS422 RX/TX driver which is half of the RS422 circuit. The other half is is what is in the picture that came with the NABU

So Computer <=> USB serial TTL <=> TTL to/from RS422 <=> NABU(RS422)

You need this part.

Greg

Thanks! I appreciate the info!

Derek

Smoke check passed. I have some special plans for this machine. I'm online!

That's an excellent setup!

Thanks!