Finished coding all opcodes.

src/chip/MOS6502/cpu.js

 }
 
 function STA(cpu){
-
+  let pmode = [null, 0x85, 0x95, null, 0x8D, 0x9D, 0x99, 0x81, 0x91, null].indexOf(cpu.__op);
+  if (ProcessOp(cpu, pmode) === true){
+    cpu.__op = -1;
+    cpu.__mem.address = cpu.__opv;
+    cpu.__mem.byte = cpu.__AR;
+  }
 }
 
 function STACK(cpu){
 }
 
 function STX(cpu){
-
+  let pmode = [null, 0x86, null, 0x96, 0x8E, null, null, null, null, null].indexOf(cpu.__op);
+  if (ProcessOp(cpu, pmode) === true){
+    cpu.__op = -1;
+    cpu.__mem.address = cpu.__opv;
+    cpu.__mem.byte = cpu.__XR;
+  }
 }
 
 function STY(cpu){
-
+  let pmode = [null, 0x84, 0x94, null, 0x8C, null, null, null, null, null].indexOf(cpu.__op);
+  if (ProcessOp(cpu, pmode) === true){
+    cpu.__op = -1;
+    cpu.__mem.address = cpu.__opv;
+    cpu.__mem.byte = cpu.__YR;
+  }
 }