Difference between revisions of "System RAM"

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The System RAM unit is the only 16-bit RAM available in the Intellivision, and it is mapped into the Intellivision [[Memory Map|memory map]] from $0200-$035F. Note that all of the System RAM is used by the [[STIC]] and the [[Executive ROM]] and is unavailable for general use by the program.<br/><br/>
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The System RAM unit is the only 16-bit RAM available in the Intellivision, and it is mapped into the Intellivision [[Memory Map|memory map]] from $0200-$035F. Note that for [[Executive ROM|EXEC]]-based programs, all of the System RAM is used by the [[STIC]] and the [[Executive ROM]] and is unavailable for general use by the program.  Programs that do not rely on the EXEC may use large portions of System RAM for their own purposes.<br/><br/>
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The System RAM has the additional responsibility of bridging between the STIC's private graphics bus and the CPU's main memory bus.
  
 
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Revision as of 02:01, 11 January 2005

The System RAM unit is the only 16-bit RAM available in the Intellivision, and it is mapped into the Intellivision memory map from $0200-$035F. Note that for EXEC-based programs, all of the System RAM is used by the STIC and the Executive ROM and is unavailable for general use by the program. Programs that do not rely on the EXEC may use large portions of System RAM for their own purposes.

The System RAM has the additional responsibility of bridging between the STIC's private graphics bus and the CPU's main memory bus.

$0200-$02EFBACKground TABle (BACKTAB)
$02F0-$02F0EXEC: Indicates the currently active cartridge header
$02F1-$0318CP1610 Stack. (Upper bound actually determined by the game software.)
$0319-$031CEXEC: Unknown use
$031D-$035CEXEC: MOB RAM data base
$035DEXEC: Current hand controller dispatch table pointer
$035EEXEC: Current random number seed
$035FEXEC: Something sound related