NAME

HsiWaitDone− wait for HSI transfer to complete
HsiWaitPPActive− wait for parallel port device to go active

SYNOPSIS

#include <hsidefs.h>

int HsiWaitDone(hsi, wm)
HSIDEV ∗hsi;
int wm;

int HsiWaitPPActive(hsi, wm)
HSIDEV ∗hsi;
int wm;

DESCRIPTION

HsiWaitDone returns to its caller when the current HSI operation is complete, or after wm milliseconds have passed.  If, upon being called, HsiWaitDone observes that the HSI is still active, it suspends the process until the HSI reports that the operation is complete.  HsiSendMem and HsiRecvMem call HsiWaitDone implicitly, so HsiWaitDone is useful principally in HSI operations where something other than the host CPU is exchanging data with the HSI (examples are the parallel port and the Pixar Fast-Disk; see HsiSetup(3H) and HsiPP(3H)).

HsiWaitPPActive returns to its caller when the external device connected to the HSI parallel port goes active (i.e., asserts the hardware PP.EXT.∗EN line), or after wm milliseconds have passed.  If, upon being called, HsiWaitPPActive observes that the parallel port device is not active, it suspends the process until the HSI reports that the parallel port device has gone active.  No time limit is imposed; however, the calling process can employ alarm(3) to detect and handle an overdue device-active situation.

RETURN VALUE

Both HsiWaitDone and HsiWaitPPActive return 0 if the desired condition happened before the time limit expired, or -1 if the time limit expired before the condition happened. 

SEE ALSO

HsiGetStatus(3H), HsiOpen(3H), HsiPP(3H), HsiSetup(3H)

HSI Tutorial

Sun Release 4.1  —  Last change: