Force Computers SYS68K/CPU-40, User Manual

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SECTION 9 APPLICATION COMMAND INTERFACE PROGRAMMING GUIDE
2-5
The least significant eight bits of the response mode contain the major interrupt number and the minor
interrupt number as shown in Figure 2. The major interrupt number specifies the interrupt class - one
of the interrupts listed above -, whereas the minor interrupt number specifies which of the interrupts in the
class is being used. Refer to table 2 for a list of the different major and minor interrupt numbers.
In contrast to the inquiry mode it is possible to specify the POLL mode; in this case the application has
to detect the completion of a command upon the state of the BUSY semaphore within the Access
Control Field of the particular Command Control Buffer.
The interrupt request level is reserved for the response mode and should be cleared.
If one of the VMEbus interrupts is specified to inform the application about the completion of a command
then bits 16 through 23 have to contain the exception vector number provided by the VMEbus interrupter
during the interrupt cycle. The most significant eight bits of the response mode are reserved and should
be cleared.