Shave a few bytes IIgs-specific startup/shutdown paths

On the IIgs the TSB/TRB opcodes can be used to save a few bytes. No functional changes.
a2stuff · Oct 24, 2024 · 0a2edbb · 0a2edbb
1 parent 16589f5
commit 0a2edbb
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Showing 2 changed files with 21 additions and 16 deletions.
diff --git a/desktop.system/desktop.system.s b/desktop.system/desktop.system.s
@@ -181,14 +181,16 @@ str_128k_required:
         ;; IIgs: Reset shadowing
         sec
         jsr     IDROUTINE
-        bcs     :+
-        lda     SHADOW
-        and     #%10000000      ; bit 7 is reserved
-        sta     SHADOW
-        lda     NEWVIDEO
-        and     #%00011111      ; bits 1-4 are reserved, bit 0 unchanged
-        sta     NEWVIDEO
-:
+    IF_CC
+        .pushcpu
+        .p816
+        .a8
+        lda     #%01111111      ; bit 7 is reserved
+        trb     SHADOW          ; ensure shadowing is enabled
+        lda     #%11100000      ; bits 1-4 are reserved, bit 0 unchanged
+        trb     NEWVIDEO        ; color DHR, etc
+        .popcpu
+    END_IF
         rts
 .endproc ; ClearScreenEnable80Cols
 

diff --git a/lib/bootstrap.s b/lib/bootstrap.s
@@ -77,14 +77,17 @@ self:
         ;; IIgs: Reset shadowing
         sec
         jsr     IDROUTINE
-        bcs     :+
-        lda     SHADOW
-        and     #%10000000      ; bit 7 is reserved
-        sta     SHADOW
-        lda     NEWVIDEO
-        and     #%00011111      ; bits 1-4 are reserved, bit 0 unchanged
-        sta     NEWVIDEO
-:
+    IF_CC
+        .pushcpu
+        .p816
+        .a8
+        lda     #%01111111      ; bit 7 is reserved
+        trb     SHADOW          ; ensure shadowing is enabled
+        lda     #%11100000      ; bits 1-4 are reserved, bit 0 unchanged
+        trb     NEWVIDEO        ; color DHR, etc
+        .popcpu
+    END_IF
+
         ;; --------------------------------------------------
         ;; Display the loading string
 retry: