NAME

hpib_send_cmnd − send command bytes over HP-IB

SYNOPSIS

int hpib_send_cmnd (eid, ca, length);
int eid, length;
char ∗ca;

HP-UX COMPATIBILITY

Level: Device I/O Library − HP-UX/EXTENDED

Origin: HP

DESCRIPTION

Hpib_send_cmnd enables you to send arbitrary  bytes of information on the HP-IB with the ATN line asserted.  This enables you to configure  and  control the  bus.  Eid is an entity identifier of an open HP-IB raw bus device file obtained from an open(2), dup(2), fcntl(2), or creat(2) call.  Ca is a character pointer to a string of bytes to be written to the HP-IB bus as commands.  Length is an integer specifying the number of bytes in the string pointed to by ca. 

The  interface   must   currently  be  the  active controller in order to send commands over the bus. 

HARDWARE DEPENDENCIES

Series 500:
Note that, for the HP 27110A/B HP-IB and the internal HP-IB (on the Model 550) interface cards, the upper bit of each byte is overwritten with a parity bit.  All commands are written with odd parity. 

RETURN VALUE

Hpib_send_cmnd returns 0 (zero) if  successful,  or −1 if an error was encountered. 

DIAGNOSTICS

Hpib_send_cmnd fails under the following circumstances, and sets errno (see errno(2)) to the value in square brackets:

eid does not refer to an open file [EBADF];

eid does not refer to an HP-IB raw bus device file [ENOTTY];

the interface is not currently the active controller [EIO]. 

Hewlett-Packard  —  last mod. May 11, 2021