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FRAM71 and RS-232 - Printable Version

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FRAM71 and RS-232 - Dave Frederickson - 02-06-2021 09:20 PM

The FRAM71 manuals demonstrate use of the module and the HP 82164A HP-IL/RS-232-C Interface. I suspect this may be faster for uploading files to the FRAM71 compared to the PIL-Box (but not easier). This is because the HP-IL messages don't need to be converted to USB.

What is the recommended 82164A setup and cable wiring? Is handshaking required?

Dave


RE: FRAM71 and RS-232 - J-F Garnier - 02-06-2021 10:10 PM

Well, the HP 82164A can be set to 19200 bps maximum, about 2 kB/s.
The PIL-Box with lastest firmware (2.1) and 230 kbps setting should easily operate at an effective 1-1.5 kB/s transfer rate, but it may be interesting to compare with the 82164A in real transfer conditions (I didn't do it).

Keep in mind that this comparison assumes binary transfer. Binary transfer is trivial with the PIL-Box (using ROMCOPY is ok), but may not be with the HP82164, and if you do ASCII transfer in the form of hex dump files, the effective transfer rate with the 82164 will be reduced by at least a factor of 2, plus the overhead on HP-71 side to rebuild the binary content.

For binary transfer you will have to disable the software handshake and use hardware handshake with proper wiring, you can look at this document, although it's a long time since I used this interface (you can guess why :-)

You will also need some utility on PC side to send the binary file over RS232, I have no suggestion here.

J-F


RE: FRAM71 and RS-232 - Hans Brueggemann - 02-07-2021 09:01 AM

moons ago, I "upgraded" a 82164A internally with an USB232R serial-to-USB module. they seem to be obsolete now.
connections between the FTDI and 82164A's UART (Rockwell R6551AP) are just 4 wires: TX, RX, VDD, GND. supply from USB is sufficient, so no more need for the wall adapter.

leaving 82164A's configuration unchanged after power-up, the PC-side USB COM-port is configured as 9600 N8 1 XON/XOFF.
a PRINTER IS 1 and then printing "1234567890ABCDEF" in a loop yields about 410 Bytes / sec.

iirc, setting the HP82164A and the PC to 19200 baud also works, but i don't remember the transfer speeds.


RE: FRAM71 and RS-232 - J-F Garnier - 02-07-2021 09:50 AM

(02-07-2021 09:01 AM)Hans Brueggemann Wrote:  moons ago, I "upgraded" a 82164A internally with an USB232R serial-to-USB module. they seem to be obsolete now.

I'm using the same UB232R module in the PIL-Box, and to my knowledge they are still available, although my favourite distributors have low stock maybe due to the current global chip shortage.
Do you have precise information?

Quote:connections between the FTDI and 82164A's UART (Rockwell R6551AP) are just 4 wires: TX, RX, VDD, GND. supply from USB is sufficient, so no more need for the wall adapter.

leaving 82164A's configuration unchanged after power-up, the PC-side USB COM-port is configured as 9600 N8 1 XON/XOFF.
a PRINTER IS 1 and then printing "1234567890ABCDEF" in a loop yields about 410 Bytes / sec.

Without handshake, no problem to send data from HP71 to PC if the HP71 loop is slow enough, but handshake may be mandatory in the other direction PC -> HP71.

J-F


RE: FRAM71 and RS-232 - Hans Brueggemann - 02-07-2021 10:02 AM

can confirm, works both ways. all examples in the FRAM71(B) manuals were done with that configuration.