Xycom XVME-240 Manual page 41

XVME-240 Manual
October, 1984
FLAG OUTPUTS REGISTER (Base Address + 86H)
Bit Bit
Bit
7 6
Writing logic " 1"
Writing logic " 0 "
To make an Output Flag transmit a logic " 1 " , a logic "1" must be written to the
corresponding bit in the Flag Outputs Register.
logic "0" a logic "0" must be written to the corresponding bit in the Flag Output
Register.
For example, to make output flags 3 and 6 a logic "1" and all others a
the module base address + 86H. This will put "1"s in bit positions 3 and 6, and "0"s in
all other locations.
On SYSRESET or Software Reset the Flag Outputs Register will contain all " 0 " s
3.4 INTERRUPTS SUMMARY
The DIO module has been designed to receive interrupt input signals from externally
connected devices in order to generate a VMEbus Interrupt Request to a system
processor. There are 8 Interrupt Input lines which logically relate to the 8 I/O ports.
Although these input lines were designed to correspond to specific I/O Ports, there are
no physical/electrical restraints placed upon their use (e.g., Interrupt Input line 1 can
be used with any of the 8 I/O ports or by itself, with no correlation to external devices
connected to the I/O ports).
Figure 3-10 shows a simplified representation of the 8 Interrupt Input lines and the
general components involved in controlling and monitoring the interrupt process. Each
Interrupt Input line has its own corresponding set of register bits and control circuitry
(represented by "black boxes"). Figure 3-10 shows an enlarged example of the logic
used by one of the Interrupt Inputs (because all of the Interrupt Inputs are identical,
only one example is needed).
Bit Bit Bit
5 4 3 2
= Flag Output of "1"
= Flag Output of " 0 "
Figure 3-9. Flags Outputs Register
Bit
Bit
1 0
Flag Output 3
Flag Output 4
Flag Output 5
Flag Output 6
Flag Output 7
To
make an Output Flag transmit a
3-14
" 0 "
write 48H to