Intermec 6200 Reference Guide

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The modem driver monitors the system voltage and refuses to enable the modem

during powerĆon operations if battery voltage is too low.  The battery level, below

which the modem cannot operate correctly, is 7.0 volts for the 6300 Computer

and 6.0 volts for the 6200 Computer.  If the modem fails to respond while an

application is improperly functioning, the application should check this voltage

level to determine if that is the cause of the problem.
Power is also be removed from the modem on any ejection of the card.  Card

power is not applied on insertion of the card.  Applications are expected to

recover from modem ejection and installation via protocol errors.

"

Once the driver is opened, power is maintained to the PC Card as long as the

card is in the slot and batteryĆlow or powerĆfail events are not detected.  On

detection of batteryĆlow or powerĆfail events, power is removed from the card and

the application is to recover from modem failure by detection of protocol errors.
It is not be possible to SUSPEND the system, while the modem driver is opened.

The modem driver suspends the request to preserve the communications session.

"

The driver supports DOS init, open, close, and IOCTL functions.  Open and close

are standard language functions.  IOCTL_IN calls (reqpk.cmd = 3) exist to get

the driver command line parameters, the modem manufacturer's ID, and the

Version 1 product information string.  The following is the structure of the DOS

request packet to the driver for IOCTL_IN (in C" format):

typedef struct

{

unsigned char reqlen;

// length of request structure

unsigned char unit;

// sub unit code for block devices only

unsigned char cmd;

// driver command

unsigned status;

// error returned by driver

long rsrv1;

// area reserved by DOS

long rsrv2;

// area reserved by DOS

unsigned char media;

// area reserved by DOS

IOCTLPARMS far* ioctl; // ioctl buffer
unsigned len;

// length of ioctl buffer

} reqpk;

The structure of an IOCTLPARMS buffer is defined as follows in C"

typedef struct {

unsigned char far *cmd;// pointer to a command value
unsigned char far *buf;// pointer to a buffer to place data in

} IOCTLPARMS;

The cmd" values are defined as follows for the modem driver.  For each

command, the buffer buf" must have the minimum size specified.  This length

must be inserted into the 

reqpk.len

 field.

Cmd Value Buffer Length Description

1

12

Return the command line parameters

2

16

Return the manufacturer ID string

3

64

Return the product version 1 information string

4

2

Return the current extended device error