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20mA Current Loop?
Posted: October 24th, 2014, 10:51 am
by toml_12953
The original 2-SIO boards had the option of interfacing with a 20mA current loop device (such as a Teletype). How about adding that optional capability to the ports on the Clone? That would eliminate having to use an RS-232/20mA converter.
Re: 20mA Current Loop?
Posted: October 24th, 2014, 6:45 pm
by AltairClone
Sure! Put this inside the Clone instead of inside the Teletype :)
http://altairclone.com/teletype.htm
Mike
Re: 20mA Current Loop?
Posted: October 25th, 2014, 11:39 am
by AltairClone
Tom, do you have a Teletype? How do you presently have the current loop interface wired? Do you have it terminate in a male DB-25 with pins 2-5 wired as recommended by MITS?
Mike
Re: 20mA Current Loop?
Posted: October 25th, 2014, 12:40 pm
by toml_12953
AltairClone wrote:Tom, do you have a Teletype? How do you presently have the current loop interface wired? Do you have it terminate in a male DB-25 with pins 2-5 wired as recommended by MITS?
Mike
I have a Teletype ASR 33 but the interface is terminated by a connector strip with four screw terminals. I could add a DB-25 easily enough, though.
Tom L
Re: 20mA Current Loop?
Posted: October 25th, 2014, 12:41 pm
by toml_12953
You mean I gotta move all those BYTE magazines outta there?!? :)
Re: 20mA Current Loop?
Posted: October 26th, 2014, 8:12 pm
by AltairClone
Regarding an RS-232 interface for the Teletype: How about an "authentic" looking board that fits inside the UCC and has a single connection to the P2 connector on the back of the UCC through which the board obtains power and the transmit/receive current loop signals? No wire cutting, AC adapters, etc. required. RS-232 connection to the board could be through a DB25 connector on the board, or maybe to be a bit more authentic, a three position terminal block?
Mike
Re: 20mA Current Loop?
Posted: October 27th, 2014, 7:26 am
by toml_12953
AltairClone wrote:Regarding an RS-232 interface for the Teletype: How about an "authentic" looking board that fits inside the UCC and has a single connection to the P2 connector on the back of the UCC through which the board obtains power and the transmit/receive current loop signals? No wire cutting, AC adapters, etc. required. RS-232 connection to the board could be through a DB25 connector on the board, or maybe to be a bit more authentic, a three position terminal block?
Mike
I'd be satisfied with that! I especially like the fact that it wouldn't require an AC adapter.
Tom L