Motorola MVME172 - Manual (Page 338)

VMEchip2 Tick Timer 1 Periodic Interrupt Example
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2. Set up local bus interrupter:
Periodic Tick Timer 1 interrupts now occur, so you need an interrupt
handler. Section 3 gives the details, as follows.
4 Tick Timer 1
Control Register
$FFF40060 (8 bits) Write $07 to this register (set bits
0, 1, and 2). This enables the Tick
Timer 1 counter to increment,
resets the count to zero on
compare, and clears the overflow
counter.
Step Register and Address Action and Reference
5 Vector Base Register
$FFF40088 (8 of 32 bits) If not already initialized by the
debugger, set interrupt base
register 0 by writing to bits 28-31.
Refer to the
Vector Base Register
description and to Table 2-3.
Local Bus Interrupter Summary,
in Chapter 2.
6 Interrupt Level Register 1
(bits 0-7)
$FFF40078 (8 of 32 bits) Write desired level of Tick Timer
1 interrupt to bits 0-2.
7 Local Bus Interrupter
Enable Register
$FFF4006C (8 of 32 bits) Set bit 24 (ETIC1) to one to
enable Tick Timer 1 interrupts.
8 I/O Control Register 1
$FFF40088 (8 of 32 bits) Write a one to bit 23 to enable
interrupts from the VMEchip2. A
zero masks all interrupts from the
VMEchip2.
Step Register and Address Action and Reference