CPU version 2, 8 bit addition only, 3byte ROM 3byte addressed MEM, glowstone 7seg hex display

New version of the already uploaded CPU map, with a few revisions. Firstly, the screen has been replaced with a shnazzy glowstone one, but the bin-hex-7seg backend remains the same. the controls for the actual CPU are as follows (right to left):

1 = control bit. determines whether the rest of the input is a number or an instruction. 0 = number 1 = instruction
2 = MEM address bit, value of 8. only 3 bytes of MEM, so this is unused
3 = MEM address bit, value of 4. same as above.
4 = MEM address bit, value of 2.
5 = MEM address but, value of 1.
6 = write value to MEM address given by above bits, or toggle screen output with MEM address of 0
7 = clear selected MEM address, or clear adder input cache with address 0.
8 = read from selected MEM address, or toggle between the two adder input caches. this must be called between inputs, else both numbers will end up in the same cache and bad things will happen.

Low numbers are on the left hand side of the inputs, so using the assignments above 1 is on input 8, 128 is on 1 etc. when using the ROM to input numbers, remember that the 1st bit cant be used for numbers. To add a number greater than 7 bits, divide it by 2 and save the answer to MEM, then call it from there.
To put numbers into the CPU, enter them into the ROM. This is the large stack or redstone and dirt nearest to the screen (other stack above the adder is working memory). The stack reads sequentially from the bottom up, and the levers show the inverse of what will be saved. So if youd like to set a bit to ON, turn the lever OFF. to save the input, put a torch on the line of redstone to the right of the levers, then remove it. the clear line is behind this, and should be operated in the same way.

Currently there isnt enough ROM to store more than 3 numbers/instructions, due to me refusing to use map editing software and too lazy to build any more :P This is enough to do a single addition and prove that it works, but if youd like to add more yourself, there is a 2-bit wide stack next to the rail line leading from the house. It should be easily visible from the house on anything higher than tiny view distance :) The circuit attached to the write control line is the ROM control circuit, this only needs to be included once per byte, and connected to the previous one as shown in the stack.

Once you have saved your program, you can run it by hitting the lever on the other side of the sea directly in front of the screen. Alternatively you can place a torch at any of the lines leading off that one. Or just break the redstone powering the clock.

If you'd like any more information, or have other questions/criticisms/compliments, leave them in the comments section and I'll reply at some point if I have an answer :) And yes, this description is probably awful, I'm not really used to writing this sort of thing :)