Path: utzoo!utgpu!cunews!mitel!testeng1!tranter
From: tranter@testeng1.misemi (Jeff Tranter)
Newsgroups: comp.sys.hp
Subject: Talking to HP-HIL bar code reader
Message-ID: <6694@testeng1.misemi>
Date: 25 Feb 91 20:06:30 GMT
Reply-To: tranter@mitel.com
Organization: Mitel Corporation
Lines: 68

We have been using an HP92916A bar code reader as part of a test
system programmed in BASIC/UX. Under BASIC, the bar code reader
behaved the same as if the input came from the keyboard.

We are now using a software platform written in C under HP-UX, and we
want to talk to the bar code reader. I have been able to read data
when the reader is set up for ASCII transmission, but for
compatibility with the BASIC software, I need to leave it set up for
USASCII keyboard mode.

The man page hil(7) says:

"Hil can only read HP-HIL keyboards in raw keycode mode. Raw keycode
mode means that all keyboard input is read unfiltered. HP-HIL
keyboards return keycodes that represent key press and key release
events".

The data I get agrees with this - it is not ASCII. I have two
questions:

1. Are the raw keycodes documented somewhere, so that I can convert
   them to ASCII? If so , where?

2. Am I going about this the wrong way?

The following is some of the code I am using to read the bar code reader.
This works when the reader was in ASCII mode.
I am running HP-UX 7.0 on a model 360.
The device file for the bar code reader looks like:

crw-rw-rw-   2 root     other     24 0x000030 Aug 14  1990 /dev/bar_code

#include <stdio.h>
#include <fcntl.h>
#include <sys/hilioctl.h>

void get_bar_code(code)
     char *code;
{
  int fd;
  unsigned char packet_length;
  unsigned char time_stamp[4];
  unsigned char poll_record_header;
  unsigned char data[20];

  /* open device file */
  fd = open("/dev/bar_code",O_RDONLY);

    do {
      read(fd, &packet_length, sizeof(packet_length));
      read(fd, time_stamp, sizeof(time_stamp));
      read(fd, &poll_record_header, sizeof(poll_record_header));
      read(fd, code, packet_length-6);
      code += packet_length-6;
    }
    /* carriage return indicates end of bar code */	
    while (*(code-1) != '\r');

    /* terminate string in null (and remove \r) */
    *(code-1) = 0;
  
    /* close device file */
    close(fd);
  }
-- 
Jeff Tranter               uunet: uunet!mitel!testeng1!tranter
Mitel Corporation       internet: Jeff_Tranter@mitel.com
Kanata, Ontario, CANADA      tel: (613) 592-2122 X4957  Fax: (613) 592-4784


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