Intel 386 User Manual page 430

Slave to clear the in-service bit.
It is also assumed that the Master is not operating in AEOI, SFNM, or
SMM. If the Master were in SMM or SFNM, a Specific EOI would have to
be used. On the other hand, if the Master were operating in AEOI mode,
no EOI signal would have to be sent.
Syntax:
Not called by user
Real/Protected Mode:
No changes required.
******************************************************************************/
void interrupt far SSIO_ISR (void)
{
Control = _GetEXRegByte(SSIOCON1);
/* If THBE is set and Transmitter Interrupts are enabled */
if ((Control & SSIO_THBE) && (Control & SSIO_TX_IE)) {
Service_THBE(); // Service routine specific to THBE interrupts
}
/* Else if RHBF is set and Receiver Interrupts are enabled */
else if ((Control & SSIO_RHBF) && (Control & SSIO_RX_IE)) {
Service_RHBF(); // Service routine specific to RHBF interrupts
}
NonSpecificEOI(); // For Slave
NonSpecificEOI(); // For Master
}/* SSIO_ISR */
/*****************************************************************************
Service_RHBF:
Description:
Service Routine for SSIO interrupts generated by the RHBF signal.
Parameters:
None
Returns:
None
Assumptions:
SYNCHRONOUS SERIAL I/O UNIT
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