INDUSTRIAL I/O PACK SERIES
AVME9675A
VMEx64 bus 6U CARRIER BOARD
Acromag, Inc. Tel: 248-295-0310
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http://www.acromag.com
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https://ww.acromag.com
interrupt acknowledge signal is consumed by the carrier board during a valid
cycle. Note that if multiple IP interrupt requests are pending, then the
carrier board will prioritize the requests based on the last interrupt serviced.
Lowest priority will be given to the last interrupt serviced.
3.13 Interrupt Configuration Example
1. Clear the global interrupt enable bit in the Carrier Board Status Register
by writing a "0" to bit 3.
2. Write interrupt vector to the location specified on the IP and perform
any other IP specific configuration required - do for each supported IP
interrupt request.
3. Write to the Interrupt Level Register to program the desired interrupt
level per bits 2,1,0.
4. Write “1” to the IP Interrupt Clear Register corresponding to the desired
IP interrupt request(s) being configured.
5. Write “1” to the IP Interrupt Enabl
e Register bits corresponding to the IP
interrupt request to be enabled.
6. Enable interrupts from the carrier board by writing a "1" to bit 3 (global
interrupt enable bit) in the Carrier Board Status Register.
3.14 Sequence of Events for an Interrupt
1. The IP asserts an interrupt request to the carrier board (asserts IntReq0*
or IntReq1*).
2. The AVME9670A carrier board acts as an interrupter in making the
VME64x bus interrupt request (asserts IRQx*) corresponding to the IP
interrupt request.
3. The VME64x bus host (interrupt handler) asserts IACK* and the level of
the interrupt it is seeking on A01-A03.
4. When the asserted VME64x bus IACKIN* signal (daisy-chained) is passed
to the AVME9670, the carrier board will check if the level requested
matches that specified by the host. If so, the carrier board will assert the
IntSel* line to the appropriate IP together with (carrier board generated)
address bit A1 to select which interrupt request is being processed (A1
low corresponds to IntReq0*; A1 high corresponds to IntReq1*).
5. The IP puts the appropriate interrupt vector on the local data bus (D00-
D07 if an D08 (O) interrupter or D00-D15 if a D16 interrupter), and