RS-232/422/485 Read Int(errupt) Status
Simulink® Real-Time™ Library for RS-232
The Read Interrupt Status block reads the interrupt status for the boards in the system.
The output for this block is a vector with one 32-bit element for each port. Each element contains two pieces of information for that port, where the 4 bytes are:
[0, 0, IIR, Reason]
The Read Interrupt Status block has signal output with the following format:
This output is a vector of integers. The values in the reason byte and their definitions are:
0 — This UART did not cause
1 — Receive characters are
2 — Transmit holding register
3 — Modem status has changed
The second byte is the value read from the Interrupt Reason Register (IIR). This register is specific to the 16450, 16550, and 16750 types of UARTs. Some bytes in this register give the active FIFO depth. Other bytes give the maximum number of characters that the transmitter empty interrupt handlers can write to the transmit FIFO.
Enter the base address of the first UART for which you want to read the interrupt status.
Enter the base address of the second UART for which you want to read the interrupt status.
If only one board of this type is in the target computer, enter
automatically locate the board.
If two or more boards of this type are in the target computer,
enter the bus number and the PCI slot number of the board associated
with this driver block. Use the format
To determine the bus number and the PCI slot number, type:
tg = slrt; getPCIInfo(tg, 'installed')