Intel PCI-7200 - Manual (Page 29)

Registers Format
• 19
O_TRG: Digital Output Trigger Signal
This bit is used to control the O_TRG output of PCI-7200, the signal is
on CN1 pin 36 of PCI-7200 or CN1 pin 26 of cPCI-7200 when
1: O_TRG 1 goes High (1)
0: O_TRG 1 goes Low (0)
u Digital I/O FIFO Status:
I_OVR: Input data overrun
1: Digital Input FIFO is full (overrun) during input data transfer
0: No input data o verrun occurred
Input data overrun occurred, the I_OVR bit is set when input FIFO is
full and there is new input data coming in. This bit can be cleared by
writing “1” to it.
O_UND: Output data FIFO is underrun
1: Output FIFO is empty during output data transfer
0: No output data underrun occurred
Output data underrun, the O_UND bit is set when output FIFO is
empty and the output request for new data, this bit can be cleared by
writing “1” to it.
3.5 Interrupt Status & Control Register (BASE + 1C)
The interrupt modes/status are set/checked through this register.
Address: BASE + 1C
Attribute: READ/WRITE
Data Format:
Byte 7 6 5 4 3 2 1 0
Base +1C SI_TO SI_REQ SO_ACK T2_EN T1_EN T0_EN II_REQ IO_ACK
Base +1D FIFOFF FIFOEF FIFORST REQ_NEG T1_T2 T0_T2 SI_T2 SI_T1
Base +1E ---- ---- ---- ---- ---- ---- ---- ----
Base +1F ---- ---- ---- ---- ---- ---- ---- ----
u Interrupt Control:
In PCI-7200, the interrupt can be triggered by many signal sources such as
O_ACK, I_REQ, timer 0, timer 1, and timer 2. The following bits control the
interrupt source:
IO_ACK: Interrupt is triggered by O_ACK signal.
1: O_ACK interrupt is enabled
0: O_ACK interrupt is disabled
II_REQ: Interrupt is triggered by I_REQ signal.
1: I_REQ interrupt is enabled
0: I_REQ interrupt is disabled