somePUNK Posted September 4, 2002 Share Posted September 4, 2002 i was reading an anolog magazeen the other night and it talked about m,emeory you can only acces but useing zpoke what the hells with thayt dose anyone know Quote Link to comment Share on other sites More sharing options...
Jetboot Jack Posted September 4, 2002 Share Posted September 4, 2002 It refers to RAM under the OS - its not avaiable to normal basic programming, but can be acessed in MC simply enough... sTeVE Quote Link to comment Share on other sites More sharing options...
+rdemming Posted September 4, 2002 Share Posted September 4, 2002 The Atari 800 XL has 64Kb ram and 24Kb rom (8Kb basic, 14 Kb OS and 2Kb selftest). Because the 6502 CPU used in the Atari 8bits can only address 64Kb, the OS and basic use some of the same addresses as the ram. This will effectively hide the ram under the OS and Basic rom. Also the range $D000-$D7FF (2Kb) is reserved for the custom chips and the ram under it cannot be accessed. Thus under basic you have 40K of usable ram (64K ram - 14K OS - 8K basic - 2K custom chips). But by disabling the Basic rom and OS rom (by (re)setting the right bits on address $D301) you can access the ram under the rom chips. Now you can access 62Kb. This only works ofcourse when the program does not use routines in the Basic or OS rom while the chips are disabled. Robert Quote Link to comment Share on other sites More sharing options...
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