Created a target and a library for the Commander X16 prototype computer.

2019-09-27 03:38:51 -04:00
parent 0896deedef
commit 18afc7c703
49 changed files with 2440 additions and 59 deletions
--- a/libsrc/cx16/set_tv.s
+++ b/libsrc/cx16/set_tv.s
@@ -0,0 +1,32 @@
+;
+; 2019-09-20, Greg King
+;
+; void __fastcall__ set_tv (unsigned char);
+; /* Set the video mode the machine will use. */
+;
+
+        .export         _set_tv
+
+        .include        "cx16.inc"
+
+
+.proc   _set_tv
+        php
+        pha
+        sei                             ; Don't let interrupts interfere
+
+        ; Point to the video output register.
+
+        stz     VERA::CTRL              ; Use port 0
+        lda     #<VERA::COMPOSER::VIDEO
+        ldx     #>VERA::COMPOSER::VIDEO
+        ldy     #^VERA::COMPOSER::VIDEO
+        sta     VERA::ADDR
+        stx     VERA::ADDR+1
+        sty     VERA::ADDR+2
+
+        pla
+        sta     VERA::DATA0
+        plp                             ; Re-enable interrupts
+        rts
+.endproc