LF: Eureka!!!! I found the CPU!!!!!!!!

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LF: Eureka!!!! I found the CPU!!!!!!!!

I am sitting here with my ti taken apart, and have examined the cpu
carefully.  It has 30 pins on each of two opposing sides, and 20 pins on the
other 2 sides.  This gives a total of 100 pins.  The numbers on the chip are
as follows:


SC414181FG16
1F54W
IEAA9545


Eureka!!!!!!!!!!!!!
I have found it.  The exact chip.  Look at the first number, see "FG16"?
There is a Motorola chip called the MC68EC020 that is in the 68000 family.
It has a 100pin FG configuration, and runs at 16 mhz.  Get it?  That means
that the TI-92 can be overclocked to 16mHz without chip replacement, for a
60% speed increase (unless of course the clock is onboard and it is already
running at 16mHz, instead of the advertised 10mHz).  I can't seem to find a
clock on the board.   There also exists a 25mHz version of the exact same
chip.  I'm looking into how to overclock.  Is it possible that there is a
turbo mode on the chip.  ie normally it runs at 10mHz, but by sending a
value to some address it jumps to 16mHz?  Either that or there is a RC
circuit or crystal on the motherboard that I don't recognize.  Exciting,
huh?  Any one up for a 25 mHz ti-92?  Rock on!
I'll keep ya updated.
Erik Buehler
Email me at: erikb@ksu.ksu.edu