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--- software:system_rom [2016/06/14 10:52]
ex_writer [System RAM Memory Cells]
+++ software:system_rom [2016/06/14 10:57] (current)
ex_writer [System RAM Memory Cells]
@@ Line 13: / Line 13: @@
 | [[:Gunfight]] | 1–46 | $17
-<WRAP todo>Better organization and context</WRAP>
+===== System Dope Vector =====
+<code z80>
+; Stuff in SYSTEM DOPE VECTOR (valid for ALL system ROMs):
+STIMER  EQU     $0200   ; Seconds and game TIMER, music
+CTIMER  EQU     $0203   ; Custom TIMERs
+FNTSYS  EQU     $0206   ; FoNT descriptor for SYStem font
+FNTSML  EQU     $020D   ; FoNT descriptor for SMaLl font
+ALKEYS  EQU     $0214   ; ALl KEYS keypad mask
+MENUST  EQU     $0218   ; head of onboard MENU STart
+MXSCR   EQU     $021E   ; address of 'MaX SCoRe' text string
+NOPLAY  EQU     $0228   ; address of 'Number Of PLAYers' string
+NOGAME  EQU     $0235   ; address of 'Number Of GAMEs' string
+</code>
 ===== System RAM Memory Cells =====
 System RAM memory definitions are located at $4FC8–4FFD in the Nutting Manual source listing (p. 14–15).
+<wrap alert>So it's possible to squash these definitions if user program overwrites these RAM areas??</wrap>
 <code z80>
@@ Line 75: / Line 90: @@
 ;
 URINAL  EQU     $4FFF   ; WASTER flushes here!
-</code>
-System [[:glossary#d|dope vector]] (valid for ALL system ROM programs)
-<code z80>
-STIMER  EQU     $0200   ; Seconds and game TIMER, music
-CTIMER  EQU     $0203   ; Custom TIMERs
-FNTSYS  EQU     $0206   ; FoNT descriptor for SYStem font
-FNTSML  EQU     $020D   ; FoNT descriptor for SMaLl font
-ALKEYS  EQU     $0214   ; ALl KEYS keypad mask
-MENUST  EQU     $0218   ; head of onboard MENU STart
-MXSCR   EQU     $021E   ; address of 'MaX SCoRe' text string
-NOPLAY  EQU     $0228   ; address of 'Number Of PLAYers' string
-NOGAME  EQU     $0235   ; address of 'Number Of GAMEs' string
 </code>