[Coco] [coco3] upscan video converter

[RJRTTY at aol.com]

In a message dated 7/17/05 8:16:26 PM Eastern Daylight Time, james at skwirl.ca 
writes:

<< 
 This may have been answered, but the ATtiny12 has in-system programmable 
 capability. There are certain electrical conditions that will trigger it. 
 A 6-pin pin-header is compatible with Atmel's AVRISP serial programmer.
 
 James >>

      Actually it's not necessary to have in-system programmability.
All the microcontroller is required to do is place coco3 system defaults or
user supplied custom values into the video chip registers when called
for at initial power up which the coco3 can't do unless you were to
put activation code in rom (DECB) or in a bootfile (OS9).  All
other I2C activity will be done by the coco3 directly.   The coco3 will also
be able to send an I2C software command for the microcontroller 
to perform a reset but that is not as important a feature as startup.

Roy