Difference between revisions of "System RAM"

From Intellivision Wiki
Jump to: navigation, search
Line 3: Line 3:
 
<table border>
 
<table border>
 
<tr><td>$0200-$02EF</td><td>BACKground TABle (BACKTAB)</td></tr>
 
<tr><td>$0200-$02EF</td><td>BACKground TABle (BACKTAB)</td></tr>
<tr><td>$02F0-$02F0</td><td>Used by the Executive ROM as a MOB GRAM Allocation Table Pointer</td></tr>
+
<tr><td>$02F0-$02F0</td><td>Used by the [[Executive ROM|EXEC]] to indicate the currently active cartridge header</td></tr>
<tr><td>$02F1-$0318</td><td>CP1610 Stack</td></tr>
+
<tr><td>$02F1-$0318</td><td>CP1610 Stack. (Upper bound actually determined by the game software.)</td></tr>
 
<tr><td>$0319-$031C</td><td>Used by the Executive ROM for unknown purposes</td></tr>
 
<tr><td>$0319-$031C</td><td>Used by the Executive ROM for unknown purposes</td></tr>
 
<tr><td>$031D-$035C</td><td>Used by the Executive ROM as a MOB RAM data base</td></tr>
 
<tr><td>$031D-$035C</td><td>Used by the Executive ROM as a MOB RAM data base</td></tr>
 
<tr><td>$035D-$035F</td><td>Used by the Executive ROM for unknown purposes</td></tr>
 
<tr><td>$035D-$035F</td><td>Used by the Executive ROM for unknown purposes</td></tr>
 
</table>
 
</table>

Revision as of 01:52, 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 all of the System RAM is used by the STIC and the Executive ROM and is unavailable for general use by the program.

$0200-$02EFBACKground TABle (BACKTAB)
$02F0-$02F0Used by the EXEC to indicate the currently active cartridge header
$02F1-$0318CP1610 Stack. (Upper bound actually determined by the game software.)
$0319-$031CUsed by the Executive ROM for unknown purposes
$031D-$035CUsed by the Executive ROM as a MOB RAM data base
$035D-$035FUsed by the Executive ROM for unknown purposes