Re: HP-97S External Printer? Message #4 Posted by BobVA on 22 Aug 2010, 10:30 p.m., in response to message #3 by Katie Wasserman
That's fun to think about. A couple of possibilities:
- It really isn't for output from the 97S, but rather is supposed to echo data sent *to* the 97S; i.e. it's listening on the 97S input bus and printing the data. Why? Perhaps for record or debug purposes? Or, if the measured parameter was intended to be included with whatever thing was being tested/measured as part of its documentation, the ink-printed paper would have been a lot more durable than the thermal print from the HP.
- You could, of course, use the four lines to shove out characters in two or three bit nibbles (using one line as a data strobe), or asynchronously using all four lines. That could then be buffered by the printer until a special "print" byte was received (or, if using two bit nibbles for data, a "print" line was strobed). But doing that AND using those lines for other signaling (for normal input via the pod) would be a mess. Seems pretty elaborate, but I guess if you needed ink hardcopy...
Separate topic: Thanks again for posting on the AAA battery pack trick for classic HP's. (Rather than glue on contacts I used some adhesive copper foil which seems to be working OK and made for a fast build.)
Regards,
Bob
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