[Coco] POKE 65495,0

Mike Pepe lamune at doki-doki.net
Fri Feb 2 11:36:47 EST 2007


jdaggett at gate.net wrote:
> On 31 Jan 2007 at 11:59, Mike Pepe wrote:
> 
>> However as I'm sure
>> someone already pointed out, reading data from DRAM will refresh that
>> entire column, so if something is running and either has properly
>> defined loops or relatively random access, the running code will keep
>> the RAM refreshed on its own
> **********
> 
> DRAM need regular refresh or they become very absent minded. You can't 
> depend on random reads and writes to the memory to ensure proper refresh. 
> Reading the DRAm I believe will refresh the ROW and not the Column. A read or 
> write to the DRAM is analogous to doing a RAS refresh. 
> 
> james 
> 

Yes, I just had it backwards. A read operation refreshes that whole row, 
not that column.

In my experience, I've run BASIC programs on a CoCo 1 for long periods 
of time in AD mode with no ill effects. Of course it's pot luck, just 
because it worked when I did it doesn't mean it'll work anywhere else.







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