Subject: RE: H89 as serial terminal

From: "Dwight K. Elvey" <[email-masked]>
Date: Mon Mar 31 11:56:00 2003

Hi
 I have a stand alone Forth ( FIG ) that I did years
ago when I first got my H89. It runs on the hard sectored
disk. I don't have any C for this machine but I do also
have the BASIC in HDOS.
 On the hardware methods, one could run both connectors,
from the terminal and CPU board to the back and make
a short external jumper cable to change it back to a computer.
This would allow one to use it either way. The only thing
one might want to open the cover for is to set the baud
rates for correct use as the computer or terminal.
Dwight

>From: "Jason J. Gullickson" <[email-masked]>
>
>Hey guys, thanks for all the info.
>
>I would prefer to go the software route (I'd prefer to run CPM and find
>a C compiler...) but I'm having a hell of a time tracking down disks for
>this thing so in the meantime I'm looking for a hardware hack to make it
>useful (or at least make it do something to freak out my fellow
>employees as my syslogs scroll across the screen of this beast), so the
>hardware solution is what I was looking for (I could have been more
>specific).
>
>On that note, if any of you know where I could find a copy of CPM and a
>compatible C compiler on hard-sectored disks, that would be greeeaaat,
>yeah.
>
>Thanks again!
>
>
>
>-----Original Message-----
>From: [email-masked] [mailto:[email-masked]]
>On Behalf Of Patrick Rigney
>Sent: Friday, March 28, 2003 1:02 AM
>To: [email-masked]
>Subject: RE: H89 as serial terminal
>
>
>> >much easier than any of the above... get a copy of MDM712 or similar 
>> >terminal emulation program.  MDM712 comes with a serial port driver 
>> >for
>>
>> Hi
>>  Why would you assume that finding and installing some software would 
>> be easier than making up a simple molex adapter connector. As I 
>> recall, it was a 9 pin molex but I could be wrong. That is all of 9 
>> wires to deal with. Dwight
>>
>
>Dwight, you're absolutly right, the software is not always "easy" to
>find and get.  Actually, check that... it's really easy to find and get
>(Google), it's just not as easy to get onto a Heath-format floppy so you
>can use it.
>
>On the other hand, I think the software approach has its merits,
>especially over the long haul.  Using a terminal emulator is a more
>permanent solution
>(IMHO) than cracking the case and swapping connectors around to
>reconfigure the device as a terminal or computer.  And, the terminal
>logic board communicates with the CPU board at 9600 baud, so if you want
>a different rate for the device you are talking to, the board has to be
>pulled and jumpers/switches changed, and then pulled and changed back if
>you want to use it as a computer again.  The three-port serial card has
>software configurable baud rates.  The hardware approach will also not
>make it emulate VT-100, which is part of what Jason had asked.  And
>since many of these programs can X/Y/Zmodem, getting other stuff onto
>the machine from there forward gets a lot simpler.
>
>While you, I, and others may feel quite comfortable mucking around with
>the innards of the beast, perhaps (and I don't know one way or another
>for sure) Jason or anyone else who might later read this thread in
>archives or digests may be less comfortable or is just working up to it,
>and so other alternatives are worth mentioning (IMHO).  Tony's hardware
>solution is good, but rerouting even one of those cables may require
>removal of the CPU and terminal logic boards, since the interconnect and
>serial cables are typically routed around the bottom edge of the two
>boards and fairly tight once home.  If you're going to go back and forth
>between terminal and computer, maybe that's a bit much in the long run.
>Add to this that the expansion boards and some of the other connectors
>attached the CPU board are all unkeyed and thus notoriously easy to
>(re)install one pin off their mating connectors, and this little
>accident can cause the kind of rapid deep frying on the CPU board that
>will turn a wonderful H89 into a dumb terminal permanently.
>
>I'm into risk management and choices.  That's all.  I certainly didn't
>intend any offense with my comment.
>
>But since we're into options... to elaborate on your and Tony's path,
>the terminal logic board's serial port is easily accessed from the rear
>of the machine--remove the lid, and as you face the back of the machine,
>it's on your left (you can sometimes read "P404" next to it).  If a
>cable is the solution of choice, then Molex directly to a DB-9 or DB-25
>(whatever the device to be connected requires) is the way to go, IMHO.
>That way, you can just open the case, pull the interconnect, connect in
>its place this new cable to the target device, and do your thing.
>Reverse to undo, lather-rinse-repeat as needed.  That won't get you
>VT-100, software transfer, or other baud rates, but it is quick and
>dirty.
>
>To that end, P404 on the terminal logic board is a 15-pin connector with
>10 pins connected.  For those interested, the pinouts are (from
>schematic w/no revision number evident, identified Heath p/n
>595-2268/595-2272):
>
>1 - (black)  ground
>2 -          no connection
>3 - (brown)  TxD
>4 -          n/c
>5 - (red)    RxD
>6 -          n/c
>7 - (orange) RTS
>8 -          n/c
>9 - (yellow) CTS
>10 -         n/c
>11 - (green) DSR
>12 -         n/c
>13 - (blue)  ground
>14 - (violet) DTR
>15 - (grey)  "RLSD/" (whazzat? anybody?)
>
>The black wire (pin 1) is up in this vertical connector.
>
>Patrick