>=20
> > If I write to location X can I not read from any location?
> > Or just not from location X?
>=20
> Simply don't read at all while a write operation is running.

 Seems wasteful. I'm pretty certain the 16F628A allows reading from other=
=20
locations than the one written to without any problems (I'll test it). As=
=20
said, there is nothing in the documentation limiting reads during writes,=
=20
and it works fine on the 16F628.

> it would require me to move up to an 18F running at >20 MHz,
> > which would certainly increase the price of the microcontroller
> > to more than $1.61, and most likely increase power
> > consumtion to above the current 13mA.
>=20
> In what way would that be a problem ?

 I'm trying to keep the total price of my system below that of a gameboy,=
=20
and the TV daughterboard below the price of the parallax version. With the=
=20
18F price would go up $1.10 and power consumption 1.6mA (less than I=20
thought). However, the EEPROM issue would still exist. Granted, I would be=
=20
able to do more fancy things, but I would be able to with the only $0.24=20
more expensive 16F688 too, and the 16F688 would at least give me a smaller=
=20
package and lower power consumption. In general, though, I'd say that a=20
higher price AND higher power consumption without gaining significant=20
benefits is a problem. I know many companies try to reduce their system by =
a=20
single resistor to lower the price.

Anyway, what is your solution ?
> Stick with the non-A 628 ?

 No... The 16F628 is more expensive and consumes a lot more power. I think=
=20
the best solution is that the user documentation will state that you can't=
=20
change a user defined character while it is displayed on screen. As said,=
=20
once I figure out how to clear the PCLATH within the time allotted, I might=
=20
switch to the 16F688 instead. I wonder how that EEPROM responds...
 Greetings,
Maarten Hofman.
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