Technical data

Preparing the Board
http://www.mcg.mot.com/literature 1-7
1
System Controller Select Header (J1)
The MVME172LX is factory-configured as a VMEbus system controller
(i.e., a jumper is installed across pins 1 and 2 of header J1). Remove the J1
jumper if the MVME172LX is not to be the system controller. Note that
when the MVME172LX is functioning as system controller, the
SCON
LED is turned on.
Note On MVME172s without the optional VMEbus interface (i.e.,
with no VMEchip2 ASIC), the jumper may be installed or
removed without affecting normal operation.
IP Bus Clock Header (J11)
J11 selects the speed of the IP bus clock. The IP bus clock speed may be
either 8MHz or the speed of the local bus clock (30MHz for the MC68060,
32MHz for the MC68LC060). The default factory configuration has a
jumper installed on J11 pins 1 and 2, denoting an 8MHz clock.
If the jumper is installed on J11 between pins 2 and 3, the IP bus clock
speed matches that of the MC68060 or MC68LC060 bus clock
(30/32MHz), thus allowing the IP module to run with a 30/32MHz MPU.
Whether the setting is 8MHz or 30/32MHz, all IP ports operate at the same
speed.
1
2
3
1
2
3
J1
1
J1
Not system controller
2
3
J1
Auto system controller
System Controller
(Factory
Configuration)