Motorola MVME162P-244 Series, Installation And Use Manual

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1-8 Computer Group Literature Center Web Site
Hardware Preparation and Installation
1
IP Bus Clock (J14)
Header J14 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 or 32MHz 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 J14 pins 2-3, the IP bus clock speed matches
that of the processor bus clock (25/32MHz), 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)
J14
Bus Clock = 8MHz
J14
Bus Clock = Proc. Bus Clock
(from MPU Bus Clock)
1 2 3 1 2 3