The comm port tests report passes and failures. The test alternates between expecting to see its data echoed back or not, depending on the state of the transmitter.

The test reports passes and failures. As long as the UART hardware responds to the XL, generating the appropriate interrupts, normally every other test passes. If all tests fail, it is not possible to tell if it is bcause the 386 is recieving no interrupts or if the appropriate states are not being found in the Interrupt status register in the UART.

Three new counters were added to help determine what is going on in the interrupt. The Number of ISR events are counted. The number of ISR pending (UART says it has an interrupt) are counted. The number of TX Empty interrupts are counted.

These counters will help determine not only if interrups are being recieved by the 386 but is the correct statuses are being reported by the UART hardware within the interrupt handler.