3 files changed, 55 insertions(+), 3 deletions(-)

M emulator/CMakeLists.txt
M emulator/main.c
M emulator/virtual_kia.c

@@ 3,7 3,7 @@ include(CTest)
 
 include_directories(${SDL2_INCLUDE_DIRS})
 
-add_executable(fbemu main.c)
+add_executable(fbemu main.c virtual_kia.c)
 target_link_libraries(fbemu lib65816a ${SDL2_LIBRARIES})
 
 add_executable(test_kia test_kia.c virtual_kia.c)

@@ 14,12 14,17 @@
 #include <lib65816/cpuevent.h>
 
 #include <SDL2/SDL.h>
+#include "virtual_kia.h"
 
 #define MAX_DISK		8
 
 /* Number of bus clock cycles per 10ms interval */
 #define THROTTLE_TICKS		40000
 
+/* Determines the bank for MVP/MVN-block I/O access */
+
+#define BLOCK_IO_BANK		0xFD
+
 static uint32_t cpu_inst_count;
 static uint32_t most_recent_insn;
 


@@ 49,6 54,7 @@ static SDL_Texture *texture;
 static uint32_t pixbuf[16384 * 8];
 static uint8_t vram[16384];
 static uint8_t key;
+static KIA_t *g_kia1;
 
 
 static void video_shutdown(void)


@@ 92,6 98,34 @@ static int video_init(void)
 }
 
 
+uint8_t kia_read(KIA_t *pk, uint32_t addr) {
+	int reg = addr & 1;
+
+	switch(reg) {
+	case 0:
+		int is_full = kia_is_full(pk);
+		int is_empty = kia_is_empty(pk);
+		return (is_full << 1) | is_empty;
+
+	case 1:
+		return kia_peek(pk);
+	}
+}
+
+void kia_write(KIA_t *pk, uint32_t addr, uint8_t _unused_value) {
+	int reg = addr & 1;
+
+	switch(reg) {
+	case 0:
+		// does nothing
+		break;
+
+	case 1:
+		kia_pop(pk);
+		break;
+	}
+}
+
 void video_write_ram(uint16_t addr, uint8_t val)
 {
 	int i;


@@ 311,10 345,14 @@ uint8_t MEM_readMem(uint32_t addr, uint32_t unused_timestamp, uint32_t emul_flag
 		most_recent_insn = addr;
 		cpu_inst_count++;
 	}
-	if ((addr >> 16) == 0xFF)
+
+	if ((addr >> 16) == BLOCK_IO_BANK)
 		addr = 0xFE00 + dma;
+
 	if ((addr >> 16) == 0xFE)
 		return video_read_ram(addr);
+	if(addr >= 0xFFF000 && addr <= 0xFFFFFF)
+		return kia_read(g_kia1, addr);
 	if (addr >= 0xFE00 && addr < 0xFF00) {
 		/* Don't cause I/O when using debug trace read */
 		if (g_debug)


@@ 334,10 372,13 @@ uint8_t MEM_readMem(uint32_t addr, uint32_t unused_timestamp, uint32_t emul_flag
 
 void MEM_writeMem(uint32_t addr, uint8_t value, uint32_t unused_timestamp)
 {
-	if ((addr >> 16) == 0xFF)
+	if ((addr >> 16) == BLOCK_IO_BANK)
 		addr = 0xFE00 + dma;
+
 	if ((addr >> 16) == 0xFE)
 		video_write_ram(addr, value);
+	else if (addr >= 0xFFF000 && addr <= 0xFFFFFF)
+		kia_write(g_kia1, addr, value);
 	else if (addr >= 0xFE00 && addr < 0xFF00)
 		io_write(addr, value);
 	else if (addr < sizeof(ram))


@@ 486,6 527,12 @@ int main(int argc, char *argv[])
 		exit(1);
 	}
 
+	g_kia1 = kia_new();
+	if(!g_kia1) {
+		perror("kia_new");
+		exit(1);
+	}
+
 	CPUEvent_initialize();
 	CPUEvent_schedule(&throttle_event, THROTTLE_TICKS, &emulate_4MHz);
 	CPU_reset();

@@ 1,3 1,8 @@
+/**
+ * @file Models the core behavior of the Keyboard Interface Adapter
+ * (KIA).
+ */
+
 #include <string.h>
 #include <stdlib.h>
 #include <stdbool.h>