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IBM PC to teltype?

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josephdaniel

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Florence, Texas, United States
Just a little curiosity mainly but if I had a teletype with a rs232 interface and a asynchronous communications card in my IBM 5160 (which I do) how hard would it be to use the teletype as a text only printer and possibly as a really loud keyboard/terminal? For some reason I don't think that it would be very hard to do and probably has been done before but the skeptic in me says that it wouldn't work for some reason or another...
 
josephdaniel said:
Just a little curiosity mainly but if I had a teletype with a rs232 interface and a asynchronous communications card in my IBM 5160 (which I do) how hard would it be to use the teletype as a text only printer and possibly as a really loud keyboard/terminal? For some reason I don't think that it would be very hard to do and probably has been done before but the skeptic in me says that it wouldn't work for some reason or another...
Click to expand...
No problem if your TTY can do 110 baud or faster; MODE and CTTY are your friends.
 
I am pretty sure it can do 110 baud I will open it up tonight and get the manufacturer and model number off of it and look it up online and see if it can. So if it was configured through a rs-232 serial port would it be able to act as a terminal for the computer printing out everything that is on the screen? if so that would be really Cool! But I don't really know what I would do with it other than using it as a printer for school papers (I already use a Selectric for that) and maybe to try to print out a BBS message if it could do that!
 
If it is RS232 and not current loop, then all you need is a null modem cable/adapter, the right baud rate at the PC end, and away you go.
 
Assuming your hardware is correctly configured and connected, use MODE to set the baud rate and parameters and then:
Use CTTY to transfer the DOS console to the TTY
- or -
Use MODE LPT= to redirect printing to the com port.
 
The original IBM async card did have support for current loop--just invert a couple of DIP jumpers. Other vendors and later IBM cards did not have CL support.
 
I am pretty sure that when I looked up tha card that I have that it supported it but I don't r remember and I didn't save it nor did I write down the model number or manufacturer of the card so i cant get the info without directly opening up my machine and pulling the card which I probably wont do until I can see if I can even get a teletype machine... I have a friend who says she might know someone who has one that I may be able to have if I drive and pick it up.
 
josephdaniel said:
I have a friend who says she might know someone who has one that I may be able to have if I drive and pick it up.
Click to expand...

Wish I had that problem. I'd love to have a ASR33 with PTP/PTR... CL or RS232 or modem!

That's part of the problem being a retro guy in north texas- people either are hording things in their garages or storage lockers (we have no basements here) or they threw it all away decades ago.

And teletypes don't tend to enjoy being shipped unless you're super awesome at crating on a pallet, it seems.

Good luck in getting one. If it is CL, be sure you know which pins are for your loop connections on the card - there is no standard for that.

The reason you don't need any tricky drivers with DOS is because DOS handles devices of standard types, including redirection and reassignment. This is why you can do things like :
Code: 
type foo.txt > lpt1:

DOS knows where LPT1 exists, same with COM1, COM2, COM3, COM4... it's just another standard IO device, so long as the card hooks into the correct IO port and IRQ.

What Chuck's telling you is you just have to reassign either your printer or console to be on that port.

After all, DOS' functional theory is heavily lifted from CP/M, and CP/M needed to have a variety of standard IO things like consoles, keyboards, modems, printers, tape punches, tape readers, etc...

It won't be the fastest printer in the world, but it will be a VERY slow console if you set it up that way.

Good luck, have fun, and don't let the magic smoke out! :)
 
I know what you mean! The pastor of my church was really into micro computing in the mid 70'2 to late 80's and oneday I was talking to his wife and she said he had a bunch of old computer stuff and she dosent know anything about it because it was all in his garage. anyways he gave it ALL to a scrapper a month before for 40.00!!! Another thing that happened not long agao my grandpa had a whole fileing cabinet of old computer programs that were on 5.25 and 8 inch floppy disks and fofr over a year i have asked him to at least let me look at some of it and he wouldn't and I went to see him a few weeks ago and I asked him again and he said he threw it all in a dumpster and he forgot that I wanted it, of all of those disks only 6 8 inch floppy disks were left behind and a few blank 5.25 disks...
Oh how I wish we had basements.
If I cant get it to work under DOS I could always try CP/M right?
TX_Dj said:
Wish I had that problem. I'd love to have a ASR33 with PTP/PTR... CL or RS232 or modem!

That's part of the problem being a retro guy in north texas- people either are hording things in their garages or storage lockers (we have no basements here) or they threw it all away decades ago.

And teletypes don't tend to enjoy being shipped unless you're super awesome at crating on a pallet, it seems.

Good luck in getting one. If it is CL, be sure you know which pins are for your loop connections on the card - there is no standard for that.

The reason you don't need any tricky drivers with DOS is because DOS handles devices of standard types, including redirection and reassignment. This is why you can do things like :
Code: 
type foo.txt > lpt1:

DOS knows where LPT1 exists, same with COM1, COM2, COM3, COM4... it's just another standard IO device, so long as the card hooks into the correct IO port and IRQ.

What Chuck's telling you is you just have to reassign either your printer or console to be on that port.

After all, DOS' functional theory is heavily lifted from CP/M, and CP/M needed to have a variety of standard IO things like consoles, keyboards, modems, printers, tape punches, tape readers, etc...

It won't be the fastest printer in the world, but it will be a VERY slow console if you set it up that way.

Good luck, have fun, and don't let the magic smoke out! :)
Click to expand...
 
Fair warning that you aren't the only guy on thre block longing for a teletype machine of any model. You better expect to pay at least $200 for one.
 
Also, be aware that teletypes come in two encoding flavors, the so-called "7 level" or the ASCII-speaking one (e.g. model 33) and the "5 level" (e.g. model 35) which uses its own code. "7 level" was typically used as a computer interface and paper-tape machinery, such as embroidery machines. "5 level" was used for TELEX, TWX and TTY for the deaf, as well as RTTY and traditional telegram use. The biggest difference is that the 7 level code, as mentioned, is 7-bit ASCII. The 5-level code consists of two character sets--one called "LTRS" or letters and the other, "FIGS" or figures. There were 2 codes reserved, each to switch between the character sets. If you happened to forget to hit either code-switch key, the other end got gibberish out.

The two types are not interchangeable and cannot read each other's paper tapes. OTOH, 5-level machines are cheaper than 7-level because there's not as much demand for them. I suspect that there are bunches of 5-level machines hiding in corporate closets and storerooms...
 
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TX_Dj said:
If it is CL, be sure you know which pins are for your loop connections on the card - there is no standard for that.
Click to expand...

If it's the actual IBM Asynchronous Communications Adapter, then it's not regular jumpers, but a little "shunt module" in the bottom right corner. There is a dot on it which goes down for CL and up for voltage interface. Also on an XT the card needs a jumper on J13 if it is to be used in slot 8. OTOH, if it's not the original IBM card with CL, then Chuck's solution looks like a painless way to go.
 
Ole Juul said:
If it's the actual IBM Asynchronous Communications Adapter, then it's not regular jumpers, but a little "shunt module" in the bottom right corner. There is a dot on it which goes down for CL and up for voltage interface. Also on an XT the card needs a jumper on J13 if it is to be used in slot 8. OTOH, if it's not the original IBM card with CL, then Chuck's solution looks like a painless way to go.
Click to expand...
As you said if it doesn't support loop back Chuck's answer looks like a good idea with out too much trouble.
 
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