BECKHOFF C1300 - Manual (Page 38)

C1300 VME to II/O Interface Unit Beckhoff II/O-System
Page 38 of 44 Version : 2.01 Date : 18.12.95
3.5. Signal state control functions
The General Control Block is used for controlling the refresh of a single signal state. It will be
refreshed and, through the ready mask, reported ready by setting the corresponding bit in the
call mask. After it was reported ready the bit must be cleared from the call mask, only then
communications can be started again. The refresh of signal states can be interrupted. When
there is a refresh in process and if there is a refresh of a higher priority called in the call mask,
the process is interrupted.
In case errors are detected in the fo-ring in a normal system run, the corresponding bits in the
error mask are set.
Address
(hex)
Contents Comment
0FFF call mask
0FFE IRQ-output
0FFD ready mask
0FFC IRQ-input
0FFB write protection The value 02h removes the write
protection
0FFA error mask
0FF9 - reserved for later use
... - - " -
0FF1 VMEbus Interrupt
Vector
Vector numbers 0h-FFh for D08
interrupter
0FF0 VMEbus Interrupt
Level
2h = IRQ1,4=IRQ2 80h=IRQ7
mask register
General Control Block