A devices/console.c

@@ -0,0 +1,25 @@ 
+#include "../xyw.h"
+
+xyw_byte console_read(xyw_byte *data, xyw_byte addr, xyw_byte *error)
+{
+    (void)error;
+    return data[addr];
+}
+
+void console_write(xyw_byte *data, xyw_byte addr, xyw_byte val, xyw_byte *error)
+{
+    (void)error;
+    data[addr] = val;
+}
+
+xyw_word console_readw(xyw_byte *data, xyw_byte addr, xyw_byte *error)
+{
+    (void)error;
+    return XYW_PEEKW(&data[addr]);
+}
+
+void console_writew(xyw_byte *data, xyw_byte addr, xyw_word val, xyw_byte *error)
+{
+    (void)error;
+    XYW_POKEW(&data[addr], val);
+}

M xyw.c → xyw.c

@@ -15,9 +15,6 @@ "AND", "IOR", "XOR", "NOT",
     "SWP", "DUP", "OVR", "ROT",
     "JMP", "JCN", "JSR", "RTS"};
 
-// Device table. Populate elsewhere or leave null for unavailable devices.
-xyw_device xyw_devices[XYW_TOTAL_DEVICES] = {0};
-
 //// Main Function
 int main(int argc, char *argv[])
 {

M xyw.h → xyw.h

@@ -12,28 +12,13 @@ #define XYW_PEEKW(d) (*(d) << 8 | (d)[1])
 #define XYW_POKEW(d, v) { *(d) = (v) >> 8; (d)[1] = (v); }
 // clang-format on
 
-/* system device */
-#define XYW_SYSTEM_STATE 0xff00
-#define XYW_SYSTEM_ERROR 0xff01
-#define XYW_SYSTEM_S 0xff02
-#define XYW_SYSTEM_U 0xff03
-#define XYW_SYSTEM_PAGE 0xff04
-#define XYW_SYSTEM_ON_ERROR 0xff05
-
-/* console device */
-#define XYW_CONSOLE_BASE 0xff10
-#define XYW_CONSOLE_INPUT 0xff10
-#define XYW_CONSOLE_OUTPUT 0xff11
-#define XYW_CONSOLE_ERROR 0xff12
-#define XYW_CONSOLE_ON_KEYPRESS 0xff13
-
 typedef unsigned char xyw_byte;
 typedef unsigned short xyw_word;
 
-typedef xyw_byte (*xyw_read)(xyw_byte addr, xyw_byte *error);
-typedef void (*xyw_write)(xyw_byte addr, xyw_byte val, xyw_byte *error);
-typedef xyw_word (*xyw_readw)(xyw_byte addr, xyw_byte *error);
-typedef void (*xyw_writew)(xyw_byte addr, xyw_word val, xyw_byte *error);
+typedef xyw_byte (*xyw_read)(xyw_byte *data, xyw_byte addr, xyw_byte *error);
+typedef void (*xyw_write)(xyw_byte *data, xyw_byte addr, xyw_byte val, xyw_byte *error);
+typedef xyw_word (*xyw_readw)(xyw_byte *data, xyw_byte addr, xyw_byte *error);
+typedef void (*xyw_writew)(xyw_byte *data, xyw_byte addr, xyw_word val, xyw_byte *error);
 
 typedef struct xyw_device
 {

M xywrun.c → xywrun.c

@@ -2,6 +2,7 @@ #include <stdio.h>
 #include "xyw.h"
 
 #include "devices/system.c"
+#include "devices/console.c"
 
 #define MEMORY_SIZE 0xffff
 #define STACK_SIZE 0xff
@@ -11,6 +12,21 @@ #define SYSTEM_MEMORY_START 0xfd00
 #define USER_STACK_START 0xfd00
 #define SYSTEM_STACK_START 0xfe00
 #define DEVICE_AREA_START 0xff00
+
+/* system device */
+#define XYW_SYSTEM_STATE 0xff00
+#define XYW_SYSTEM_ERROR 0xff01
+#define XYW_SYSTEM_S 0xff02
+#define XYW_SYSTEM_U 0xff03
+#define XYW_SYSTEM_PAGE 0xff04
+#define XYW_SYSTEM_ON_ERROR 0xff05
+
+/* console device */
+#define XYW_CONSOLE_BASE 0xff10
+#define XYW_CONSOLE_INPUT 0xff10
+#define XYW_CONSOLE_OUTPUT 0xff11
+#define XYW_CONSOLE_ERROR 0xff12
+#define XYW_CONSOLE_ON_KEYPRESS 0xff13
 
 typedef enum
 {
@@ -52,7 +68,12 @@ {
     return (addr - DEVICE_AREA_START) / 16;
 }
 
-static inline xyw_byte get_device_port(xyw_word addr)
+static inline xyw_byte *get_device_data(xyw_word addr)
+{
+    return xyw_devices[get_device(addr)].data;
+}
+
+static inline xyw_byte get_device_address(xyw_word addr)
 {
     // Should return a number between 0 and 15, add validation
     xyw_byte port = (addr - DEVICE_AREA_START) % 16;
@@ -76,8 +97,8 @@ {
             *error = XYW_ERROR_DEVICE_UNAVAILABLE;
             return (xyw_word)-1;
         }
-        xyw_byte dev_addr = get_device_port(addr);
-        return xyw_devices[dev_num].readw(dev_addr, error);
+        xyw_byte dev_addr = get_device_address(addr);
+        return xyw_devices[dev_num].readw(get_device_data(addr), dev_addr, error);
     }
     return XYW_PEEKW(&xyw_memory[addr]);
 }
@@ -92,8 +113,8 @@ {
             *error = XYW_ERROR_DEVICE_UNAVAILABLE;
             return;
         }
-        xyw_byte dev_addr = get_device_port(addr);
-        xyw_devices[dev_num].writew(dev_addr, val, error);
+        xyw_byte dev_addr = get_device_address(addr);
+        xyw_devices[dev_num].writew(get_device_data(addr), dev_addr, val, error);
         return;
     }
     XYW_POKEW(&xyw_memory[addr], val);
@@ -109,8 +130,8 @@ {
             *error = XYW_ERROR_DEVICE_UNAVAILABLE;
             return (xyw_byte)-1;
         }
-        xyw_byte dev_addr = get_device_port(addr);
-        return xyw_devices[dev_num].read(dev_addr, error);
+        xyw_byte dev_addr = get_device_address(addr);
+        return xyw_devices[dev_num].read(get_device_data(addr), dev_addr, error);
     }
     return xyw_memory[addr];
 }
@@ -125,8 +146,8 @@ {
             *error = XYW_ERROR_DEVICE_UNAVAILABLE;
             return;
         }
-        xyw_byte dev_addr = get_device_port(addr);
-        xyw_devices[dev_num].write(dev_addr, val, error);
+        xyw_byte dev_addr = get_device_address(addr);
+        xyw_devices[dev_num].write(get_device_data(addr), dev_addr, val, error);
         return;
     }
     xyw_memory[addr] = val;
@@ -305,6 +326,16 @@ // Read value from address
 #define READ(addr) (w ? readw(addr) : (xyw_byte)xyw_memory[addr])
 // Write value as word or byte depending on width flag 'w'
 #define WRITE(addr, val) w ? writew(addr, val) : write(addr, (xyw_byte)(val))
+
+//// Initialize devices
+
+xyw_device xyw_devices[XYW_TOTAL_DEVICES] = {
+    // System device (not implemented yet)
+    {&xyw_memory[0xff00], system_read, system_write, system_readw, system_writew},
+    // Console device
+    {&xyw_memory[0xff10], console_read, console_write, console_readw, console_writew},
+    // ...
+};
 
 // clang-format on
 int xyw_run(const char *input)