implement lpoke/lpeek with compound instructions

MEGA65 · Jun 1, 2023 · 87ae766 · 87ae766
1 parent 49cae7e
commit 87ae766
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Showing 3 changed files with 28 additions and 7 deletions.
diff --git a/cc65/include/memory.h b/cc65/include/memory.h
@@ -28,10 +28,11 @@ extern struct dmagic_dmalist dmalist;
 extern unsigned char dma_byte;
 
 void mega65_io_enable(void);
-unsigned char qpeek(long address);
 unsigned char lpeek(long address);
 unsigned char lpeek_debounced(long address);
+unsigned char dma_peek(long address);
 void lpoke(long address, unsigned char value);
+void dma_poke(long address, unsigned char value);
 void lcopy(long source_address, long destination_address,
            unsigned int count);
 void lfill(long destination_address, unsigned char value,

diff --git a/cc65/src/memory.c b/cc65/src/memory.c
@@ -21,7 +21,7 @@ void do_dma(void)
   POKE(0xd705U, ((unsigned int)&dmalist) & 0xff); // triggers enhanced DMA
 }
 
-unsigned char lpeek(long address)
+unsigned char dma_peek(long address)
 {
   // Read the byte at <address> in 28-bit address space
   // XXX - Optimise out repeated setup etc
@@ -65,7 +65,7 @@ unsigned char lpeek_debounced(long address)
   return db1;
 }
 
-void lpoke(long address, unsigned char value)
+void dma_poke(long address, unsigned char value)
 {
 
   dmalist.option_0b = 0x0b;

diff --git a/cc65/src/memory_asm.s b/cc65/src/memory_asm.s
@@ -1,12 +1,32 @@
-        .export _qpeek
+        .export _lpoke, _lpeek
 
-        .importzp sreg,tmp1,tmp2,tmp3,tmp4
+        .p02
 
-        .p4510
+        .importzp sp,sreg,tmp1,tmp2,tmp3,tmp4
+        .import incsp4
 
-.proc	_qpeek: near
+        .p4510
 
 .segment	"CODE"
+
+.proc	_lpoke: near
+        pha
+        neg
+        neg
+        .p02
+        lda sp
+        .p4510
+        neg
+        neg
+        sta tmp1
+        ldz #$00
+        pla
+        nop
+        sta (tmp1),z
+        jmp incsp4
+.endproc
+
+.proc	_lpeek: near
         sta tmp1
         stx tmp2
         lda sreg