My plan is to let an old PLC "print" to a terminal program in a laptop.
Then save, maybe edit for readability, format, save, and print.
Probably it just need to receive whatever is coming, as ASCII.
From an example in old manual, it looks like it is not using graphic characters, plus it have a setting for 8 or 7 bit ASCII.
What Mageia serial terminal program is suitable?
Can I use USB-serial dongle or do it need a hardware serial port?
(I only have real serial port on my 32 bit Thinkpad T43)
How do I enable and configure a serial port on Mageia?
For printing, programmer manual conveniently list it use signals RX, TX, RTS, CTS, so I can monitor and check with an old serial cable LED dongle.
And a not fully described setting for specifically using the EPSON RX80 or FX 80 printer, and also describes DIP switches settings on printer. One thing I note is that host is sending LF but no note on CR, we will see. 80 characters per line.
For PC communication DIP switches can set baud from 300 to 38k4, and 7 or 8 bit, 1 or 2 stop bits, even or odd parity. (not all combinations though)
(But I have not yet found a compatible PC program, see below)
Anyway I guess DIP settings work the same for printing.
Situation
A customer have a machine with old PLC in operation.
(- Now, after I have repaired the internal power supply...)
They want me to make a program backup and printout.
Then edit it slightly to modify operation slightly.
And also arrange a complete physical PLC spare.
Problem: Hitachi HIZAC EM is old stuff.
(machine mechanicalli is good for a few more decades)
Wow: I got hold of the Hitachi HIZAC EM hardware - complete rack with correct modules plus one extra!
- including programming manual book!
- And handheld programmer PGMJ-R2, and manual for it as pdf found on internet.
- And extra memory module
So I start playing and learning.
The programmer is of latest shiniest version so apart from cassette recorder interface for program storage, it also have a serial port.
It specifies to use original IBM PC 5150/5160 and a programming software J-LDR, from IBM (??), I can not find more than a bunch of other looking for it on forums...
I even found traces of a MS windows program have existed, also asked on forum like others, no response for a month.
Me and others in same situation have not managed to retrieve any yet...
Of course I also asked Hitachi bu web form, no response at all for a month. (Do they think that will make me buy new stuff from them?) Sigh.
As usual, the first thing breaking is software support :/ How hard can it be to *not* throw away an existing program file??
I still keep trying other former suppliers...
Anyway, luckily the hand held programmer is surprisingly effective to use. Efficient UI and procedure design.
However, for understanding the machine program I really need a printout to read and annotate...
That also it is good enough to classify as a program backup.
(Additionally I will have program duplicated in both the old and "new" PLC, plus extra memory module.)
Wonderful: The programmer actually can print both assembly and ladder output to a serial printer
- but of specified type from the early eighties.