CPU Program:Can't move data in/out of the CPU via address bus and data ports.

[Squeakyneb]

I am trying to learn to use the CPU, but it isnt working

start:
    jmp main

calls:
    input:
        in eax,8
        in ebx,9
        ret
    output:
        out 0,eax
        out 1,ebx
        ret

main:
    call input
    call output
    jmp main

Address Bus Settings:

Address	Offset	Size
1	0	8
2	8	8
3	16	8
4	24	8

I'm starting by taking input and sending it out to the display straight away. The displays are screens(the screens that display 2 numbers). Using a debugger, I can see that the data port I am using for input (wired to Add. bus memory2) is getting the numbers from the input device(a numpad, dupe attatched) but the data port linked to the displays (add.bus mem1) is staying at all zeros.

Dupes attatched, images for those who don't want the dupes. BPU is Bennys Processing Unit, by the way. The other dupe is the numpad I made for it. Would have been smarter to use a wired numpad, but i already had that built.

Thanks for the help everyone.

[Whodunnit]

Why are you using address bus for this program? just link one data port to the address bus slot on the cpu.

a single databus can be used for input and output...

however, this should still be working , have you tried

input:
mov eax, port8;
mov ebx,port9;
ret
output:
mov port0, eax;
mov port1, ebx;

ret


personally i would remove the "calls:" label and just have a comment.
also try with semicolons after instructions.

[Black Phoenix]

Nah, it's okay to leave "calls" label. I like how your code looks like. Are you sure you wired address bus to IOBUS?

[Squeakyneb]

Ok, I'll try those.

I used the address bus because I plan on expanding on this contraption, so I am using the first data port for display, second for input, third and fourth in case I need them.

EDIT:
@BP:Thanks. I have the address bus wired to IOBUS.

UPDATE:
I got it working. New Code

start:
    jmp main

calls:
    input:
        mov eax,port8
        mov ebx,port9
        ret
    output:
        mov port0,eax
        mov port1,ebx
        ret

main:
    call input
    call output
    jmp main

Why could I not use in and out??

[Whodunnit]

maybe a failure for that syntax with more than one data port.

[Whodunnit]

swapping registers doesn't work because there is no opcode for it.

I think whitespace is ignored by the assembler.

Edit by l3ulletje:
if ( this post != sense ) {
It has been made to reply on a post I made without noticing the thread got replies.
Therefore my post was total bullcrap, so I deleted that post again.
} else {
ignore this edit
}

[Black Phoenix]

XCHG swaps two values or registers

[Squeakyneb]

Why are we exchangeing values in registers? Am I missing something?

How would I use a register in the port number?

mov eax,port#ebx

Would that work?

I am thinking of using a "Device Connection Initiation Protocol" or DCIP. In short, each devices last port (port7 for device 0, port15 for device 1 etc.) will be used to identify the device. CPU will regularly scan these ports and establish what device, if any, is present, and store the necessary data.

So if there is a numpad on device 3 (ports 24-31) the CPU will store 3 numbers in memory: 111(code to identify start of device data) 1(device number for numpads)3(device number).

When the program calls for a numpad it will search a specified section of memory for 111, then check if the next value is 1 (device is a numpad) and then gets the device number if it is a numpad.

In short, I want to make hot-swappable devices.

Any opinions?

To use the device: (device number)*8+(device port)=(actual port). Device3 port2 would be 3*8+2=26. I think.

[Fizyk]

"in" and "out" should work, I use them and everything is ok...
If you want to use ports with numbers in registers, you need "in" and "out", or... you could use the negative address space. AFAIK, address -1 is port0 etc., so let's say you have port number in ebx:

out ebx,eax //should output eax to port ebx

//should be equivalent to this:
neg ebx
dec ebx
mov #ebx,eax

[Squeakyneb]

Negative numbers are port space? Sounds odd, but I suppose it makes sense, because I think that using positive numbers represents memory.

EDIT:
I'm trying to use variables, but its not working. I tried "alloc curpos" but when it hits that instruction it puts out error 2(end of program?). What's going on?