Tesla-A4D4 Micro Micromanagement Computer

Description:
	The T-A4D4 is the second smallest computer on Powder Toy at 98x52 pixels in size.
	The operations the A4D4 has available to it are limited, but it makes up for it in its small size and high speed.


Physical:
	The T-A4D4 Only has three registers: PC, A, and B, A being the ALU. And it only has one flag, the Carry flag. 

ROM:
	The A4D4 has two 4-bit, 16 byte banks of embedded Read Only Memory.
	The active bank switches when the Program Counter overflows, or the BS instruction is encountered.
	
	The ROM is stored in an 8-bit format, with the low nybble for bank one and the high nybble for bank two.
	Example:
		If you wanted to store an '8' in bank 2 and an 'F' in bank 1, you would write an "8F" to the first pixel of the drive.

Pinout:
	The T-A4D4 has eight pins for I/0

	0:Input bit 3
	1:Input bit 2
	2:Input bit 1
	3:Input bit 0
	4:Output bit 3
	5:Output bit 2
	6:Output bit 1
	7:Output bit 0

Commands:
	Nop
		No Operation

	bs
		Bank Switch

	ld
		Load a value into a register.

	Add
		Add a value to A. The result is stored in A.

	Inv
		Invert a value or flag

	Inc
		Increment a register's value

	jp
		Jump to a point in the program

	Stop
		Stop the computer


	Opcodes:

	|Decimal
	|  |Hexidecimal
	|  | |Binary
	|  | |    |Effects flag
	|  | |    | |Length in bytes
	|  | |    | | |Mneumonic
	|00|0|0000|0|1|Nop
	|01|1|0001|0|1|bs
	|02|2|0010|0|1|ld Output,a
	|03|3|0011|0|1|ld b,Input
	|04|4|0100|0|2|ld a,d4
	|05|5|0101|0|2|ld b,d4
	|06|6|0110|0|1|ld a,b
	|07|7|0111|0|1|ld b,a
	|08|8|1000|c|1|add a,b
	|09|9|1001|c|1|Inv a
	|10|A|1010|c|1|inc a
	|11|B|1011|c|1|inc b
	|12|C|1100|0|1|jp a4
	|13|D|1101|0|1|jp nc,a4
	|14|E|1110|c|1|Inv c
	|15|F|1111|0|1|Stop