Counter Registers; Geographical Address Register; Table 1-21. Tick Timer Compare Registers; Table 1-22. Tick Timer Counter Registers - Motorola MVME3100 Programmer's Manual

Chapter 1 Board Description and Memory Maps
When programming the tick timer for periodic interrupts, the counter should be cleared to zero by
software and then enabled. If the counter does not initially start at 0, the time to the first interrupt may
be longer or shorter than expected. The rollover time for the counter is 71.6 minutes.

Table 1-21. Tick Timer Compare Registers

REG
BIT
FIELD
OPER
RESET

Counter Registers

When enabled, the tick timer Counter register increments every microsecond. Software may read or
write the counter at any time.

Table 1-22. Tick Timer Counter Registers

REG
BIT
FIELD
OPER
RESET

Geographical Address Register

The VMEbus Status register in the TSi148 provides the VMEbus geographical address of the
MVME3100. This register reflects the inverted states of the geographical address pins at the 5-row, 160-
pin P1 connector.
22
MVME3100 Programmer's Guide (V3100A/PG1)
Tick Timer 1 Compare Register - 0xE202 0014 (32 bits)
Tick Timer 2 Compare Register - 0xE202 0024 (32 bits)
Tick Timer 3 Compare Register - 0xE202 0034 (32 bits)
Tick Timer 4 Compare Register - 0xE202 0044 (32 bits)
31
Tick Timer Compare Value
R/W
0
Tick Timer 1 Counter Register - 0xE202 0018 (32 bits)
Tick Timer 2 Counter Register - 0xE202 0028 (32 bits)
Tick Timer 3 Counter Register - 0xE202 0038 (32 bits)
Tick Timer 4 Counter Register - 0xE202 0048 (32 bits
31
Tick Timer Counter Value
R/W
0
0
0