Xycom XVME-240, Руководство пользователя

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XVME-240 Manual
October, 1984
FLAG OUTPUTS REGISTER (Base A 86H)
Bit Bit
Bit Bit Bit Bit Bit
Bit
7 6 5 4 3 2 1 0
Flag Output 3
Flag Output 4
Flag Output 5
Flag Output 6
Flag Output 7
Writing logic " 1" = Flag Output of "1"
Writing logic " 0 " = Flag Output of " 0 "
Figure 3-9. Flags Outputs Register
To make an Output Flag transmit a logic " 1 " , a logic "1" must be written to the
corresponding bit in the Flag Outputs Register.
To
make an Output Flag transmit a
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
" 0 "
write 48H to
the module base a 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).
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