22 Dec
2012
22 Dec
'12
4:37 p.m.
On 12/22/2012 07:20 PM, Chuck Guzis wrote:
"Still"? Have they gone out of style or something?
-Dave
--
Dave McGuire, AK4HZ
New Kensington, PA
But, if you
want to re-code the RO, then either you have to find a way of
making the ROM i nthe R2D2 chip invisible to the processor (which is not
trivial, given that the address and data is transered serially over the
same line (ISA) and that this singal is needed fro the otehr sections of
R2D2) or you haev to somehow rebuild the functions of the RAM and display
driver. Then you have to interface an EPROM or sinmialr to the Nut bus,
this is essetially the same as making a ROM box or MLDL unit for an HP41.
And finally you have to fit it all in the case.
You know, I still find calculators darned handy,