10. Trouble Shooting the Mega-Midget Racer™
FUNCTIONAL PROBLEMS:
Symptom:
Accelerator does not function, will not boot-up, system crashes when using the
“68020 Analyzer.”
Check: Jumper block
W4
, if 68000 is installed on the accelerator.
Fix:
Remove the “
E Sync
” jumper if 68000 is installed.
Check: Installation of the 68000 on accelerator for bent pins or pins not making good
contact with the 68000 socket.
Fix:
Reseat the 68000 observing the polarity per Figure 1 of the User’s Manual.
Make sure all pins make good contact with the socket.
Check: Jumper block
J P 3
for correct setting. When the jumper is in the “
SYS
”
position, both the 68030 and coprocessor are clocked at the frequency of the oscillator in the
U6
socket. When the jumper is in the “
OSC
” position, the 68030 is clocked at the frequency of
the oscillator in the
U6
socket and the coprocessor is clocked at the frequency of the oscillator
in the
U5
socket. (If
JP3
is in the “
OSC
” position, no oscillator is present in
U5
and a
coprocessor is installed, the system will crash).
Fix:
Change jumper to “
SYS
” position or use an appropriate oscillator in the
U5
socket. Install the oscillators per Figure 1 to assure correct polarity. Assure that all pins
make good contact with the socket.
Check: Correct orientation of all user installable components per Figure 1.
Fix:
Assure that all socketed parts are firmly seated in their proper socket in
the correct polarity orientation as shown in Figure 1.
Symptom:
Intermittent or random system crashes with frozen ICONS.
Check: Power supply voltage for m4.85 volts.
Fix:
Have a qualified service representative adjust the power supply voltage to
5.0 volts, + .15, - .15 volts.
32-BIT MEMORY PROBLEMS:
Symptom:
Software Error, Task Held, Guru Message when SROM or ADDRAM are installed.
Check: Jumper block
W3
. A “
512K
” jumper should not be installed.
Fix: Remove the “
512K
” jumper if installed in
W3
.
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