rsv

rsv

Request Service/Set or Change Serial Poll Status Byte

Type

Serial poll function

Syntax

rsv [spbyte]<CR>

Purpose

You can use rsv if the GPIB-RS232/485/422 is not the GPIB Controller and you want to request service from the Controller using the Service Request (SRQ*) signal. The GPIB-RS232/485/422 provides a user-defined status byte when the Controller serial polls it.

Remarks

The argument spbyte is a numeric string specifying the decimal value of the new GPIB-RS232/485/422 serial poll response byte.

The serial poll response byte is the status byte the GPIB-RS232/485/422 provides when serial polled by another device that is CIC. If bit 6 (hex 40 or RQS bit) is also set, the GPIB-RS232/485/422 requests service by asserting the SRQ* line.

If you call rsv without an argument, the GPIB-RS232/485/422 returns a numeric string containing the decimal value of its serial poll status byte.

The assignment made by rsv remains in effect until you call rsv again, call onl, or turn off the GPIB-RS232/485/422.

Example 1

Request service with serial poll response of 0x46.

char  buffer [] = "rsv \\x46\r";
viWrite(instr, buffer, strlen(buffer), &retCount);

Example 2

Query the current serial poll status byte.

char  buffer [] = "rsv\r";
char rsvString[6];
memset(rsvString,0,6);
viWrite(instr, buffer, strlen(buffer), &retCount);
viRead(instr, rsvString, 6, &retCount);
printf("S Mode serial poll response byte is: 0x%X\n",atoi(rsvString));