Measurement Computing COM232/8AT - Manual (Page 5)

1000-0901, rev 1.1 March 1998 COM232/8AT User’s Guide 5
Interrupts
The COM232/8AT is capable of supporting 11 interrupt levels (IRQ 2 thru IRQ 7, IRQ 10 thru
IRQ 12, IRQ 14, and IRQ 15). All channels share the same interrupt. You can change the interrupt
selection by repositioning the jumper on JP9. The interrupt positions for JP9 are indicated in the
figure, COM232/8AT Layout Reference, on page 6.
Scratchpad or Interrupt ID Register Selection
Jumper JP10 is used to select the Scratchpad Register, or the Interrupt ID Register. The JP10 setting to
be used is based on the operating system and the software interfacing with the COM232/8AT. The
following table indicates settings for Windows95 and WindowsNT, version 4.0 applications.
System JP10 Setting
Windows95 Scratchpad
WindowsNT, version 4.0 Interrupt ID
Note: The Scratchpad and Interrupt ID registers are discussed in more detail on page 14.
Note: Do not confuse the Interrupt ID Register with the Interrupt Identification Register.