Add INPUT and OUTPUT descriptions

README.md

@@ -72,8 +72,37 @@ Multiply two numbers, and outputs to the memory address in the third parameter.
 
 ### 03 - INPUT
 
+Takes input from either the runtime input array, or from the console, depending on the Input Mode Map. The Input Mode Map is an array of value, either `INPUT_FROM_CONSOLE` or `INPUT_FROM_RUNTIME_STACK`, provided to the computer before running. Each time an INPUT opcode is encounter, an Input Mode is shifted off of this array. Once the array is empty, any further INPUT opcodes encounter will assume `INPUT_FROM_RUNTIME_STACK` unless the `inputFromConsole` option is true.
+
+If the input is set to come from the runtime input array, and the array is empty, the computer will _pause_ execution until either the `Run` function for the `Input` functions are called on the computer.
+
+The output position is always used in Immediate Mode.
+
+| Forms | Description |
+| ----- | ----------- |
+|     3 | Receive input |
+|    03 | Receive input |
+
+|       Parameters | Description |
+| ---------------- | ----------- |
+|  Output position | The memory address to store the result in |
+
 ### 04 - OUTPUT
 
+Outputs either a value from a memory address, or a literal value. This output is initially sent to an `outputValues` array. If the computer's `outputToConsole` option is true, then the output is instead displayed in the console.
+
+If the computer has an `outputComputer` set, then the output is instead sent to the output computer through an `Input` call to that computer.
+
+| Forms | Description |
+| ----- | ----------- |
+|     4 | Output a value in Position Mode |
+|    04 | Output a value in Position Mode |
+|   104 | Output a value in Immediate Mode |
+
+|       Parameters | Description |
+| ---------------- | ----------- |
+|  Operand 1 | The number, or memory address of the number, to output |
+
 ### 05 - JUMP IF TRUE
 
 ### 06 - JUMP IF FALSE