Question about DMP--105 support

[keenerb]

Is it intended to be used with an actual Tandy 1000 card-edge connector or from a standard Centronics LPT card?

http://www.oldskool.org/guides/tvdog/1kfaq.html#II.H.4

It's always been risky to connect an early DMP printer, specifically due to the 5v on pin 18.

I'd like to give it a shot but frankly I'm just a little confused as to what the expected configuration is...

[RWAP]

Not having too much information about the TRS-80, we were expecting that you would just use a normal centronics connector.

I can see there is a warning about +5V on pin 18 - we have jumpers on the v4 Retro-Printer to disconnect pin 13, 18 or pin 32 on the centronics connector, so assume this would resolve the issue if you used a cable from the edge connector. If we get double spacing because of pin 14, we can probably overcome this in software, but pin 31 and pin 33 needing to be swapped would be somewhat of an issue as the grounds are dealt with on the centronics port.

[keenerb]

The TRS-80 and Tandy 1000 are different beasts but the DMP-105 was a common accessory for either.

It has a RS232 serial interface so I'll probably look at giving that a shot first. If the centronics connector grounds the INIT line then I bet that's a problem indeed, would need some sort of custom adapter to work around that, which was pretty common to do back in the day...

[RWAP]

We can emulate serial port using a usb to serial adapter into the raspberry pi

[keenerb]

Does it require a specific usb-serial adapter? Is there a special build required?

[RWAP]

Does it require a specific usb-serial adapter? Is there a special build required?

It just needs a quality USB-Serial adaptor - we have had good results using this one from Amazon

However, the main issue is getting the right serial port settings - as there is such a range of competing variables.

A special build is not required - if you want the serial port settings, you have to email us directly as it is still very much in the beta test phase.