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Serial port downloads from (Linux) PC to HP-41

Posted by Tony Duell on 10 Feb 2001, 2:59 p.m.

Here's my file on downloading from a (linux) PC to an HP41 using the serial interface and extended I/O module. You'll have to modify the PC configuration instructions for your OS, but I can't tell you how to do it...

Transfering progrmas between an HP41 and a PC using a serial interface

This document describes how to use the HP82164 HPIL-RS232 interface to connect an HP41 calculator (fitted with the HP82160 HPIL interface and the Extended I/O module) to a Linux PC, and to transfer programs in both directions between them.

Throughout this document, the PC's serial port will be named /dev/cua0 . Change this as appropriate, of course.

Hardware connections

Connect the HPIL side of the HP82164 to the HP41's IL module in the usual way.

The jumper plug inside the HP82164 interface should be set to the DTE position. See the interface's user manaul for more details of this.

Connect the HP82164's RS232 port to the PC using a standard PC modem cable and a special adapter. The latter is needed owing to the rather strange hardware handshaking of the HP82164, and the following diagram gives the necessary wiring :

   PC                         HP82164
   (DB25-S)                   (DB25-S)

Prot Gnd 1 )-------------------( 1 Prot Gnd

TxD 2 )-------------------( 3 RxD

RxD 3 )-------------------( 2 TxD

RTS 4 )-------------------( 5 CTS

CTS 5 )-------------------( 20 DTR

DSR 6 )--+----------------( 4 RTS | CD 8 )--+

Sig Gnd 7 )-------------------( 7 Sig Gnd

DTR 20 )----------------+--( 6 DSR | +--( 8 CD

Configuring the interfaces

On the PC, turn off buffering and enable hardware handshaking by typing :

stty raw crtscts </dev/cua0

On the HP41, load the SETRS program and run it to set the HP82164 interface to hardware handshake mode and to make it the primary device. A binary file of this program is given in hardware/setrs.p41 in the lif_utils distibution, and is given as a listing below :

0001  LBL "SETRS"
0002  66
0004  SELECT
0005  CF 17
0006  REMOTE
0007  "SL2"
0008  OUTA
0009  "LI5"
0010  OUTA
0011  "C0"
0012  OUTA
0013  NOTREM
0014  END

Transfering a program from the HP41 to the PC

On the PC type :

inp41 < /dev/cua0 >program_file

where program_file is the filename that you want the binary program stored in. Alteratively you can pipe the output of inp41 to prog41 to get a text listing by typing :

inp41 < /dev/cua0 | prog41

On the HP41:

Put the name of the program to send (or more exactly one of the global labels in that program) in the alpha register.

Then execute : OUTP

When the program has transfered, the PC should display

checksum good

and the program will be stored in the specified file

Transfering a program from the PC to the HP41

On the PC type :

outp41 < program_file >/dev/cua0

where program_file is the name of a file containing an HP41 program.

The input to outp41 can be piped from lifget (for example) in the standard way to transfer a file from a lif disk image. For example :

lifget -f disk1 PROG | outp41 > /dev/cua0

will transfer the file PROG from the lif disk image disk1.

On the HP41:

GTO .. to pack program memory and create a dummy program at the END.

then execute : INP

When the program has transfered, the X-register display will return. CAT 1 to check that the program has loaded.

A. R. Duell, 2-Oct-2000.
This file is part of the LIF Utilities distribution and has been placed under the GNU Public License version 2.0


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