diff --git a/vm.md b/vm.md
index cefe248..9f28924 100644
--- a/vm.md
+++ b/vm.md
@@ -43,32 +43,32 @@ CPU flags are addressed by bit index, going from right to left.
 
 ## Arithmetic
 
-Arithmetic instructions store their result in the last register specified.
+Arithmetic instructions store their result in the first register specified.
 
 * Add
     * **Params**: REG1, REG2
-    * `REG2 = REG1 + REG2`
+    * `REG1 = REG1 + REG2`
 * Mul
     * **Params**: REG1, REG2
-    * `REG2 = REG1 * REG2`
+    * `REG1 = REG1 * REG2`
 * Div
     * **Params**: REG1, REG2
-    * `REG2 = REG1 / REG2`
+    * `REG1 = REG1 / REG2`
 * Mod
     * **Params**: REG1, REG2
-    * `REG2 = REG1 % REG2` (exact semantics TBD)
+    * `REG1 = REG1 % REG2` (exact semantics TBD)
 * Neg
     * **Params**: REG1
     * `REG1 = REG1 * -1`
 * And
     * **Params**: REG1, REG2
-    * `REG2 = REG1 & REG2`
+    * `REG1 = REG1 & REG2`
 * Or
     * **Params**: REG1, REG2
-    * `REG2 = REG1 | REG2`
+    * `REG1 = REG1 | REG2`
 * Xor
     * **Params**: REG1, REG2
-    * `REG2 = REG1 ^ REG2`
+    * `REG1 = REG1 ^ REG2`
 * Shl
     * **Params**: REG1, REG2
     * `REG1 = REG1 << REG2`
@@ -124,9 +124,8 @@ Arithmetic instructions store their result in the last register specified.
     MEM[REG2] = REG1;
     ```
 * StoreImm32
-    * (hw = half word)
-    * **Params**: REG1, IMM_HW
-    * `REG1 = IMM_HW`
+    * **Params**: REG1, IMM_32
+    * `REG1 = IMM_32`
 * MemCopy
     * **Params**: REG1, REG2
     * `MEM[REG1] = MEM[REG2]`