The bits in the control word have the following meaning:
Bit no. Type of interrupt
0 = ’1’ Cyclic timed interrupts, fixed period
1 = ’1’ Clock-controlled interrupt
2 = ’1’ Process interrupts
3 = ’1’ Delayed interrupt
4 to 15 Reserved: these bits must be ’0’
As long as a bit is set to ’1’, the corresponding interrupt is disabled.
2. ACCUs
2a)
ACCU-2-L
Function no.,
Permitted values: 1, 2 or 3 where:
1: The contents of ACCU 1 are loaded in the
control word.
2: All the bits marked ’1’ in the mask in
ACCU 1 are set to ’1’ in the control word.
The new control word is loaded in ACCU 1
3: All the bits marked ’1’ in the mask in
ACCU 1 are set to ’0’ in the control word.
The new control word is loaded in ACCU 1
2b)
ACCU 1
New control word or mask depending on the required function.
OB 142: "Delay All Interrupts" On/Off
CPU 948 Programming Guide
C79000-G8576-C848-04
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