Motorola MVME162P-242, Installation And Use Manual

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Preparing the Board
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1
IP Bus Clock (J13)
J13 selects the speed of the IP bus clock. The IP bus clock speed may be
8MHz or it may be set synchronous to the processor bus clock (25MHz for
the MC68040 and MC68LC040). The default factory configuration has a
jumper installed on pins 1-2, denoting an 8MHz clock.
If the jumper is installed on J13 pins 2-3, the IP bus clock speed matches
that of the processor bus clock (25MHz), allowing the IP module to pace
the MPU. Whether the setting is 8MHz or the processor bus clock speed,
all IP ports operate at the same speed.
!
Caution
The setting of the IP32 bit in the Control/Status registers (Petra IP2 sector,
register at offset $1D, bit 0) must correspond to that of the jumper. The bit
is cleared (0) for 8MHz, or set (1) to match the processor bus clock speed.
If the jumper and the CSR bit are not configured the same, the board may
not run properly.
(Factory configuration)
J13
Bus Clock = 8MHz
J13
Bus Clock = Processor Bus Clock
(from MPU Bus Clock)
1 2 3 1 2 3