Hi, i am writing a polling code for PS2 mouse, but i am receiving strange packet format. Anywhere i found that standard sequence is: Control flags, x delta, y delta, but i am receiving the three bytes in the order: x delta, control flags, y delta.
I am confused a lot. Soem body have pass the same experience, or i am wrong at code...? Here is the read code, i use the actual var assigment but in comments the documented one.
The previous code is the default initialization comands for PS2 (F6,F4)
And the rest is for visualize mousex, mousey and control in binary format. I know the packet is right because of this and i am able to see buttons state data when are used.

Code:

mousepoll: in      al,64h                 test    al,1                 jz      mousepoll                 test    al,20h          ; Test for mouse data                 jz      mousepoll                 cmp     [secuencia],0   ; Check packet sequence                 jne     @f                 in      al,60h                 mov     [mousey],al     ; read first packet(should be control flags but results in _y delta)                 inc     [secuencia]                 jmp     mousepoll             @@: cmp     [secuencia],1   ; Check packet sequence                 jne     @f                 in      al,60h                 mov     [control],al    ; read second packet(should be _x delta but results in control flags)                 inc     [secuencia]                 jmp     mousepoll             @@: in      al,60h                 mov     [mousex],al     ; read third packet(should be _y delta but results in _x delta)                 mov     [secuencia],0

May be i am missunderstanding ps2 protocol?

what is "secuencia" initialized to?

When a packet is marked as ready, you can read all data bytes at once without re-polling, so there should be no reason to force the sequence.

Quote:

When a packet is marked as ready, you can read all data bytes at once without re-polling, so there should be no reason to force the sequence.

you need to poll for the next byte. in fact, I've had issues in this respect with my driver. VirtualBox allows you to read in each byte as easily as a sequence of in instructions yet VMware (and my real hardware) simply ends up reading in the same byte each time.

Hello BAiC! secuencia is initialized to zero. I copy the code, it is just a simple floppy boot code. I am testing it on qemu:

Code:

use16 org 7C00h           mov     di,1660              mov     ax,0b800h            mov     es,ax            @@: in  al,64h               test    al,2                 jnz     @b                           mov     al,0A8h         ; Activar el dispositivo auxiliar PS2                out     64h,al       @@:     in      al,64h               test    al,1                 jz      TestOut              in      al,60h               jmp     @f        TestOut: test  al,2                 jnz     @b           @@: in  al,64h               test    al,2                 jnz     @b           mov     al,0D4h         ; Indicar el envío de un comando al dispositivo             out     64h,al       @@: in  al,64h               test    al,2                 jnz     @b           mov     al,0F6h         ; Enviar comando reset(para inicializar el dispositivo)              out     60h,al       @@:     in      al,64h               test    al,1                 jz      @b           in      al,60h           cmp     al,0xAA              je      @f           @@: in  al,64h               test    al,2                 jnz     @b           mov     al,0D4h         ; Indicar el envío de otro comando          out     64h,al       @@: in  al,64h               test    al,2                 jnz     @b           mov     al,0F4h         ; Activar el ratón          out     60h,al      mousepoll: in    al,64h               test    al,1                 jz      mousepoll                test    al,20h               jz      mousepoll                ; Here starts the problematic part, just at sequence reading                         cmp     [secuencia],0                jne     @f           in      al,60h               mov     [mousey],al          inc     [secuencia]          jmp     mousepoll        @@: cmp [secuencia],1                jne     @f           in      al,60h               mov     [control],al                 inc     [secuencia]          jmp     mousepoll        @@: in  al,60h               mov     [mousex],al          mov     [secuencia],0            push    di                           mov     al,[control]                 call    bin8                 add     di,144               mov     al,[mousex]          call    bin8                 add     di,144               mov     al,[mousey]          call    bin8                 pop     di                        push    di           add     di,20                test    [control],1          jz      @f           mov     [es:di], word 0100111001001001b          mov     [es:di+2], word 0000111000100000b                mov     [es:di+4], word 0000111000100000b            @@:     test    [control],2          jz      @f           mov     [es:di], word 0000111000100000b          mov     [es:di+2], word 0000111000100000b                        mov     [es:di+4], word 0100111001000100b            @@:     test    [control],4          jz      @f           mov     [es:di], word 0000111000100000b          mov     [es:di+2], word 0100111001000011b                mov     [es:di+4], word 0000111000100000b            @@: pop di           jmp     mousepoll        bin8:       mov     cx,8             @@:     shl     al,1                 jc      uno          mov     [es:di],word '0 '              add     di,2                 loop    @b           ret  uno:        mov     [es:di],word '1 '              add     di,2                 loop    @b           ret       secuencia db 0      control db 0          mousex db 0          mousey db 0 times 510-($-$$) db 0             dw 0xAA55

the error that you describe sounds like you haven't read in all of the data bytes from the initialization sequence.

immediately before the "mousepoll" label you are issuing Command 0xF4. That command has a response byte which you'll need to poll for. I'm looking at my driver for that type of command and it has an interrupt which expects to read in 1 byte. my driver is an Interrupt-powered State Machine so it looks considerably different from what you have.

Thank's a lot BAiC! It works fine now!!!!
Just adding a read poll before label:

Code:

@@:     in      al,64h               test    al,1                 jz      @b           in      al,60h