On 09/03/2011 07:14 PM, Hársfalvi Levente wrote: > Speaking of sram cells... You can possibly light some clue on a small > detail that I couldn' have understood so far (...and you couldn't, it > might still be a warning about what's likely to be seen somewhere in the > TED). > > As you say, the sram cells generally don't lose their content (because, > as I get it, they're built up like a classic, bistable sram cell, ie. > from two inverters). > > One would suppose, flags must be implemented in a similar fashion ( some > bistable). Not necessarily. The sram that holds character pointer and attribute data has to stay stable for a long time (8 character rows, much longer if the RAM was filled at the end of the last character row) before it gets overwritten. Certain flags that, if everything works according to spec, are constantly refreshed, don't need an SRAM cell. They can be implemented like the registers in the NMOS 6502 which also loses data if clocked to slow. Gerrit Message was sent through the cbm-hackers mailing listReceived on 2011-09-03 18:00:15
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