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HAL_UARTInterruptID
Hardware Abstraction Layer
HAL entry points from RISC OS
ยป HAL_UARTInterruptID
HAL_UARTInterruptID
(HAL entry #79)
int HAL_UARTInterruptID(int port)
| Entry | |
|---|---|
| port | Port number to query |
| Exit | |
|---|---|
| - | Returns the highest prioirty interrupt currently asserted. |
Use
This is an internal call for use by the DualSerial? module and should not be used by user code. Instead of calling the HAL directly, user code should interact with the Serial* entries that DualSerial creates in DeviceFS.
Returns the highest priority interrupt currently asserted. In order of priority:
- 3 => Receiver Line Status (Cleared by HAL_UARTReceiveByte/HAL_UARTLineStatus)
- 2 => Received Data Available (Cleared by reading enough data)
- 6 => Character Timeout (received data waiting)
- 1 => Transmitter Holding Register Empty (Cleared by this call)
- 0 => Modem Status (Cleared by HAL_UARTModemStatus)
- -1 => No Interrupt
The Modem Status interrupt occurs when the CTS, DSR or DCD inputs change, or when RI goes from high to low (ie bits 0 to 3 of HAL_UARTModemStatus are set).