On Sep 1, 2005, at 6:05 AM, Maarten Hofman wrote:

> The EEPROM is used to house the user defined graphics. If a user 
> decides to
> create their own graphic, they can send it to the system using RS-232 
> and it
> is stored in EEPROM. However, while this is happening, the system still
> needs to update the TV screen (keeping synchronization is the most 
> important
> task of the system, everything else is secondary), and therefore 
> access the
> EEPROM if there are any user defined characters on screen.

While I sympathize (somewhat, anyway) with highly tuned code that
has stopped working due to the differences between 628 and 628a, I
gotta argue with your assumption there.  Surely downloading user
graphics happens seldom enough that you can blank the screen while
they are being saved to EEPROM?  I'm reminded of the timex-sinclair
zx80 that would blank the screen a lot while running the basic
interpreter.  It wasn't great, but it was usable...

BillW
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