Provided by: libgpib-doc_4.3.7-5_all 
NAME
ibrsp - read status byte / serial poll (device)
SYNOPSIS
#include <gpib/ib.h>
int ibrsp(int ud, char *result);
DESCRIPTION
ibrsp() obtains the status byte from the device specified by ud. The status byte is stored in the
location specified by result.
If automatic serial polling is enabled on the board controlling the device, the status byte is
automatically read and queued whenever the device requests service. If the status byte queue is not empty
ibrsp() obtains the status byte information from the queue. If the queue is empty the status byte is
obtained by serial polling the device. Automatic serial polling is controlled with ibconfig(). The
contents of the status byte returned in result are device specific. Refer to the device manufacturer's
documentation for details. For devices conforming to the IEEE488.1 or 2 specification the bits defined in
the table below are available if enabled in the device's Status Byte Enable register.
Table 10. Standard IEEE.488 GPIB status byte bits
┌──────────┬───────┬──────────────────────────────┐
│ constant │ value │ description │
├──────────┼───────┼──────────────────────────────┤
│ IbStbRQS │ 0x40 │ The request service bit is │
│ │ │ set when device asserts │
│ │ │ RQS. It is │
│ │ │ cleared by serial polling │
│ │ │ the device. │
│ │ │ Supported by devices │
│ │ │ conforming to IEEE 488.1 or │
│ │ │ IEEE 488.2. │
├──────────┼───────┼──────────────────────────────┤
│ IbStbESB │ 0x20 │ The event-status bit is set │
│ │ │ when there are one or more │
│ │ │ bits set in the │
│ │ │ device's Standard Event │
│ │ │ Status Register. It │
│ │ │ is cleared by reading the │
│ │ │ Standard Event Status │
│ │ │ Register. For │
│ │ │ devices conforming to IEEE │
│ │ │ 488.2 only. │
├──────────┼───────┼──────────────────────────────┤
│ IbStbMAV │ 0x10 │ The message available bit │
│ │ │ indicates whether or not the │
│ │ │ device's data │
│ │ │ output queue is empty. │
│ │ │ Whenever the device has │
│ │ │ data available, │
│ │ │ this bit will be set. It is │
│ │ │ cleared when the │
│ │ │ output queue is empty. The │
│ │ │ queue is emptied by reading │
│ │ │ data from the │
│ │ │ device with │
│ │ │ ibrd() for │
│ │ │ example. For devices │
│ │ │ conforming to IEEE 488.2 │
│ │ │ only. │
└──────────┴───────┴──────────────────────────────┘
RETURN VALUE
The value of ibsta is returned.
COPYRIGHT
Copyright © 2003-2006, 2008 Frank Mori Hess
linux-gpib 4.3.7 11/28/2025 IBRSP(3)