Added SWAP_RESTORE option and FAR_POINTER().

f256lib/bitmap.c

@@ -25,9 +25,6 @@
 #include "dma.h"
 
 
-#define EIGHTK      0x2000
-
-
 static uint16_t _MAX_X;
 static uint16_t _MAX_Y;
 static uint32_t _PAGE_SIZE;
@@ -61,6 +58,8 @@ void bitmapClear(void) {
 	POKE(SWAP_SLOT, block);
 	for (c=0; c<5120; c++) mem[c] = _color;
 
+	SWAP_RESTORE_SLOT();
+
 	SWAP_IO_SHUTDOWN();
 #endif
 }
@@ -132,6 +131,8 @@ void bitmapLine(uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2) {
 		bitmapPutPixelIOSet(x, y);
 	}
 
+	SWAP_RESTORE_SLOT();
+
 	SWAP_IO_SHUTDOWN();
 }
 
@@ -139,6 +140,7 @@ void bitmapLine(uint16_t x1, uint16_t y1, uint16_t x2, uint16_t y2) {
 void bitmapPutPixel(uint16_t x, uint16_t y) {
 	SWAP_IO_SETUP();
 	bitmapPutPixelIOSet(x, y);
+	SWAP_RESTORE_SLOT();
 	SWAP_IO_SHUTDOWN();
 }
 

f256lib/dma.c

@@ -64,5 +64,5 @@ static void dmaWait(void) {
 	POKE(DMA_CTRL, 0);
 
 	// Then wait for a VBL because two DMAs per frame will crash.
-	graphicsWaitVerticalBlank();
+	//graphicsWaitVerticalBlank();
 }

f256lib/f256.c

@@ -104,6 +104,17 @@ void f256Init(void) {
 }
 
 
+void f256Reset(void) {
+	asm("sei");
+	POKE(MMU_MEM_BANK_7, 7);
+	POKE(0xD6A2, 0xDE);
+	POKE(0xD6A3, 0xAD);
+	POKE(0xD6A0, 0xF0);
+	POKE(0xD6A0, 0x00);
+	asm("JMP ($FFFC)");
+}
+
+
 byte FAR_PEEK(uint32_t address) {
 	byte block;
 	byte result;
@@ -114,6 +125,7 @@ byte FAR_PEEK(uint32_t address) {
 	address &= 0x1FFF;  // Find offset into this block.
 	POKE(SWAP_SLOT, block);
 	result = PEEK(SWAP_ADDR + address);
+	SWAP_RESTORE_SLOT();
 
 	SWAP_IO_SHUTDOWN();
 
@@ -131,6 +143,7 @@ uint16_t FAR_PEEKW(uint32_t address) {
 	address &= 0x1FFF;  // Find offset into this block.
 	POKE(SWAP_SLOT, block);
 	result = PEEKW(SWAP_ADDR + address);
+	SWAP_RESTORE_SLOT();
 
 	SWAP_IO_SHUTDOWN();
 
@@ -138,6 +151,21 @@ uint16_t FAR_PEEKW(uint32_t address) {
 }
 
 
+void *FAR_POINTER(uint32_t address) {
+	byte block;
+
+	// This only works if we use slot 5 and don't restore it after swapping.
+#if SWAP_SLOT == MMU_MEM_BANK_5
+	block = address / EIGHTK;
+	address &= 0x1FFF;  // Find offset into this block.
+	POKE(SWAP_SLOT, block);
+	return (void *)address;
+#else
+	return 0;
+#endif
+}
+
+
 void FAR_POKE(uint32_t address, byte value) {
 	byte block;
 
@@ -147,6 +175,7 @@ void FAR_POKE(uint32_t address, byte value) {
 	address &= 0x1FFF;  // Find offset into this block.
 	POKE(SWAP_SLOT, block);
 	POKE(SWAP_ADDR + address, value);
+	SWAP_RESTORE_SLOT();
 
 	SWAP_IO_SHUTDOWN();
 }
@@ -162,6 +191,7 @@ void FAR_POKEW(uint32_t address, uint16_t value) {
 	address &= 0x1FFF;  // Find offset into this block.
 	POKE(SWAP_SLOT, block);
 	POKEW(SWAP_ADDR + address, value);
+	SWAP_RESTORE_SLOT();
 
 	SWAP_IO_SHUTDOWN();
 }
@@ -174,6 +204,9 @@ void FAR_POKEW(uint32_t address, uint16_t value) {
 int f256main(int argc, char *argv[]);
 int main(void) {
 	f256Init();
-	return f256main(kernelArgs->common.extlen / 2, (char **)kernelArgs->common.ext);
+	f256main(kernelArgs->common.extlen / 2, (char **)kernelArgs->common.ext);
+	f256Reset();
+	return 0;
 }
+#define main f256main   // This one is needed if you build f256.c included with your code.
 #endif

f256lib/f256.h

@@ -58,11 +58,13 @@ typedef unsigned char bool;
 #define false  0
 
 
-// Our stuff.
+// Near memory slot to use for far memory swapping.
+#ifndef SWAP_SLOT
 #define SWAP_SLOT  MMU_MEM_BANK_5
+#endif
 
-// This is an attempt to allow us to free up slot 5 and use slot 6 for paging
-// RAM in and out.  ***TODO*** Currently, it does not work.
+// This is an attempt to allow us to free up slot 5 and use other slots
+// for swapping RAM in and out.  ***TODO*** Currently, it does not work.
 #if SWAP_SLOT == MMU_MEM_BANK_6
 
 #define SWAP_IO_SETUP() \
@@ -91,10 +93,18 @@ typedef unsigned char bool;
 
 #endif
 
+#ifdef SWAP_RESTORE
+#define SWAP_RESTORE_SLOT()   POKE(SWAP_SLOT, SWAP_SLOT - MMU_MEM_BANK_0)
+#else
+#define SWAP_RESTORE_SLOT()
+#endif
+
 #define SWAP_ADDR  ((uint16_t)(SWAP_SLOT - MMU_MEM_BANK_0) * (uint16_t)0x2000)
 
 
 // Things not in the Merlin defs.
+#define EIGHTK      0x2000
+
 #define TEXT_MATRIX  0xc000  // I/O Page 2
 
 #define RAST_ROW_L   0xd01a
@@ -221,15 +231,17 @@ typedef struct colorS {
 #endif
 
 
-void     f256Init(void);
-byte     FAR_PEEK(uint32_t address);
-uint16_t FAR_PEEKW(uint32_t address);
-void     FAR_POKE(uint32_t address, byte value);
-void     FAR_POKEW(uint32_t address, uint16_t value);
+void      f256Init(void);
+void      f256Reset(void);
+byte      FAR_PEEK(uint32_t address);
+uint16_t  FAR_PEEKW(uint32_t address);
+void     *FAR_POINTER(uint32_t address);
+void      FAR_POKE(uint32_t address, byte value);
+void      FAR_POKEW(uint32_t address, uint16_t value);
 
 
 #ifndef WITHOUT_MAIN
-#define main f256main
+#define main f256main   // This one is needed if you build f256.c as it's own compilation unit.
 #endif
 
 

llvm-mos-sdk-patches/mos-platform/f256k/settings.ld

@@ -1 +1 @@
-__f256_start = 0x2000;
+__f256_start = 0x0300;