M xyw.c → xyw.c

@@ -7,7 +7,7 @@ 
 // Instruction mnemonics definition
 const char xyw_instructions[][4] = {
     "BRK", "PSH", "POP", "???",
-    "LDP", "LDR", "STP", "STR",
+    "LDB", "LDW", "STB", "STW",
     "INC", "DEC", "SHL", "SHR",
     "ADD", "SUB", "MUL", "DIV",
     "EQU", "NEQ", "GTH", "LTH",

M xywrun.c → xywrun.c

@@ -288,23 +288,25 @@ //// "Microcode" similar to Uxn's, to be used with above macros
 // Get argument from x or stack
 #define ARGX rx ? (w ? *xw : *x) : (w ? us_popw() : us_pop())
 // Get a byte argument from x or stack
-#define ARGXB rx ? *x : us_pop()
+#define ARGXB (rx && !!a && !!b) ? *x : us_pop()
 // Get a word argument from x or stack
-#define ARGXW rx ? *xw : us_popw()
+#define ARGXW (rx && !!a && !!b) ? *xw : us_popw()
 // Get argument from y or stack
 #define ARGY ry ? (w ? *yw : *y) : (w ? us_popw() : us_pop())
 // Get arguments from x/y or stack
 #define ARGXY rx ? (rx ? (w ? *xw : *x) : (w ? us_popw() : us_pop())) : (ry ? (w ? *yw : *y) : (w ? us_popw() : us_pop()))
 // Get a byte argument from x/y or stack
-#define ARGXYB rx ? (rx ? *x : *y) : us_pop()
+#define ARGXYB (rx && !!ry) ? (rx ? *x : *y) : us_pop()
 // Get a word argument from x/y or stack
-#define ARGXYW rx ? (rx ? *xw : *yw) : us_popw()
+#define ARGXYW (rx && !!ry) ? (rx ? *xw : *yw) : us_popw()
 // Push a value to stack
 #define PUSH(n) do { if (w && !!rx && !!ry) { us_pushw(n); } else { us_push(n); } } while(0)
 // Pop value from stack
 #define POP() (w ? us_popw() : (xyw_word)us_pop())
 // Write a byte or word to the specified direct page or absolute address 
-#define WRITE(addr, val) ((w && !!a && !!b)? writew(addr, val) : write(addr, val))
+#define WRITE(addr, val) ((w)? writew(addr, val) : write(addr, val))
+// Read a byte or word (depending on w) from the specified direct page or absolute address
+#define READ(addr) ((w)? readw(addr) : read(addr))
 
 
 //// Initialize devices
@@ -347,10 +349,10 @@ /* BRK */ case 0x00: return 0; // Halting execution for now
             /* PSH */ OPC_PSH(0x01);
             /* POP */ OPC_POP(0x02);
             ///* LDR */ OPC_R1(0x03, PUSH(READ(a))); // TBD
-            /* LDP */ OPC_SR1(0x04, , PUSH(read(ARGXYB)));
-            /* LDR */ OPC_SR1(0x05, , PUSH(readw(ARGXYW)));
-            /* STP */ OPC_SR2(0x06, WRITE(DIRECT_PAGE | ARGXB, ARGY));
-            /* STR */ OPC_SR2(0x07, WRITE(ARGXW, ARGY));
+            /* LDB */ OPC_SR1(0x04, , us_push(w ? READ(ARGXYW) : READ(DIRECT_PAGE | ARGXYB)));
+            /* LDW */ OPC_SR1(0x05, , us_pushw(w ? READ(ARGXYW) : READ(DIRECT_PAGE | ARGXYB)));
+            /* STB */ OPC_SR2(0x06, write(DIRECT_PAGE | ARGXB, ARGY));
+            /* STW */ OPC_SR2(0x07, writew(ARGXW, ARGY));
             /* INC */ OPC_IDC(0x08, +1);
             /* DEC */ OPC_IDC(0x09, -1);
             /* SHL */ OPC_SR2(0x0A, PUSH(b << a));