kb2syd
Veteran Member
Reading over some old archives I found. Does anyone remember this tip for the model 4?
SIMPLE SPEED MOD
==================
Here's a simple modification for your Model 4. It requires no
additional hardware and it will bring your computer to its true
4Mhz speed. I should add that I have used my machine for about
5 years after making this simple change with no ill effects.
One thing you must consider: This modification has worked on my
machine, but I cannot guarantee the results on yours. If my
memory serves me right, credit for this tip should be given to
Larry Paine.
Whith that out of the way, open your machine; if you need me to
tell you how to do it, you better get someone else to do it.
Remove the shield that covers the computer's main board in the
read of the machine.
Locate the Z-80 chip (CPU). Pull it out carefully. Bend back
pin 27. Reinsert the chip making sure that pin 27 does not make
contact with anything.
Replace the shield and the machine's cover. That's it!
What the modification does is to remove the wait states in the
Z-80, which are not really needed in your Model 4. To test the
difference it makes, run a program such as CLKSPD/CMD before
and after the modification.
Luis M. Garcia-Barrio
Sysop of 8/N/1 #4
555-555-5555
SIMPLE SPEED MOD
==================
Here's a simple modification for your Model 4. It requires no
additional hardware and it will bring your computer to its true
4Mhz speed. I should add that I have used my machine for about
5 years after making this simple change with no ill effects.
One thing you must consider: This modification has worked on my
machine, but I cannot guarantee the results on yours. If my
memory serves me right, credit for this tip should be given to
Larry Paine.
Whith that out of the way, open your machine; if you need me to
tell you how to do it, you better get someone else to do it.
Remove the shield that covers the computer's main board in the
read of the machine.
Locate the Z-80 chip (CPU). Pull it out carefully. Bend back
pin 27. Reinsert the chip making sure that pin 27 does not make
contact with anything.
Replace the shield and the machine's cover. That's it!
What the modification does is to remove the wait states in the
Z-80, which are not really needed in your Model 4. To test the
difference it makes, run a program such as CLKSPD/CMD before
and after the modification.
Luis M. Garcia-Barrio
Sysop of 8/N/1 #4
555-555-5555