Building PS2 to Amiga mouse adapter

[Johan1973]

Hello there.
I Have been trying to build this adapter;
http://ps2m.sotchenko.ru/version.html

However, I can not get it to work. And I have no idea where it fails. Is there anyone here that has built this circuit successfully?

[kipper2k]

There are better circuits than that available. The one you shown has stability issues. I have (hopefully) my parts i need to complete mine this weekend and will post the schematic and firmware for it

[demolition]

Originally Posted by Johan1973

Hello there.
I Have been trying to build this adapter;
http://ps2m.sotchenko.ru/version.html

However, I can not get it to work. And I have no idea where it fails. Is there anyone here that has built this circuit successfully?

I have built that exact one and it's works great for me. Haven't seen any stability issues so far. My first one didn't work however, but was because I chose the wrong clocking method when I burned the PIC, so it was set up to RC oscillator instead of Xtal.

[Johan1973]

Maybe I am burning the software wrong, because I have never used PICs before. My programmer is a TL866 and the software I use is MiniPro programmer. Can you tell me how I am supposed to configure it for xtal or oscillator?

kipper2k: I am looking forward to your schematics and firmware

All I want to do is to use my old Logitech Trackball Marble for my amigas

[demolition]

I use WinPIC and it looks like this.

You should have a similar setting in your program. XT is crystal.

[Johan1973]

These are the configurable settings I have;

[hooverphonique]

so you probably need to set those 14 configuration word bits correctly.. set them so you get a value of 3FFD like demolition has (try checking bit 1).

I'm not proficient in PIC, so I don't know if the user id values matter as well, but I suspect they don't in this case.

[Johan1973]

After setting every bit except one, I get a response, it pushes both mouse buttons all the time which brings me to the boot menu on the amiga.

[hooverphonique]

does your software report the same config word as demolitions? Looking at your screenshot I would think you only have to set bit 1, not all but bit 1 (fuses, which I guess they are, are often inverted).

[Johan1973]

No matter what bits I set, I can not get 2007 to be 3FFD.

I am completely new to PICs, this is the very first project I am doing with one, so it is a steep learning curve.

EDIT:
Turned out the "mouse buttons pressed" was a misswiring. Corrected the wiring, and it does nothing now. This is the settings I set;

[demolition]

I might have remembered incorrectly regarding the correct oscillator setting as that screenshot was taken from another machine (I need to get to an XP machine for writing so it wasn't available).

According to the documentation Osc should be set to HS which is 3FFE.
You will get this by only enabling bit 0 and disabling the rest.
Alternatively you can try setting it to XT (3FFD) which is just bit 1 on.

[Johan1973]

Originally Posted by demolition

I might have remembered incorrectly regarding the correct oscillator setting as that screenshot was taken from another machine (I need to get to an XP machine for writing so it wasn't available).

According to the documentation Osc should be set to HS which is 3FFE.
You will get this by only enabling bit 0 and disabling the rest.
Alternatively you can try setting it to XT (3FFD) which is just bit 1 on.

Both those configurations do not work.

[demolition]

Does it say 3FFE and 3FFD in the corner when you set those values? Because it seems weird to me that no tick would mean =1.

Have you tried reading back the contents of the PIC to verify that everything was written correctly?

Next, check the wiring again. If you have a voltage meter, check the voltage on all points where there should be a supply.

[Johan1973]

Originally Posted by demolition

Does it say 3FFE and 3FFD in the corner when you set those values? Because it seems weird to me that no tick would mean =1.

Have you tried reading back the contents of the PIC to verify that everything was written correctly?

Next, check the wiring again. If you have a voltage meter, check the voltage on all points where there should be a supply.

Yes, it says that.
There is voltage on every pin except the VSS of course. Cant say more than that since I can not see pulses. No idea if the crystal is oscillating at all.

[demolition]

If you have an oscilloscope, you should be able to see a 4MHz signal on one of the clockpins. If not, then something is wrong, so check the crystal connections and the two small capacitors connected to it. Also check if there is a clock on any of the two Osc configs above. The clock is the first thing to get going as it is independent from the rest of the wiring.

[Loedown]

PIC is indeed a steep learning curve, one issue I see with that circuit is that MCLR isn't tied high through a pull up resistor to Vdd, I don't have the PIC84A literature handy but a value of 10K to 40K should be fine. You could also simplify the circuitry by using a PIC that has an inbuilt oscillator block. I am busy like hell but if you need to know more about PIC ask, my email should be in my profile.

[Loedown]

Originally Posted by demolition

If you have an oscilloscope, you should be able to see a 4MHz signal on one of the clockpins. If not, then something is wrong, so check the crystal connections and the two small capacitors connected to it. Also check if there is a clock on any of the two Osc configs above. The clock is the first thing to get going as it is independent from the rest of the wiring.

OSC Out is usually RA7 and it's Fosc / 4.

[Johan1973]

I do not have an oscilloscope. So I can not figure out if the crystal is oscillating. Crystals have given me a hard time in the past.

[Loedown]

Originally Posted by Johan1973

I do not have an oscilloscope. So I can not figure out if the crystal is oscillating. Crystals have given me a hard time in the past.

Write code to make a led flash on one of the unused pins, keeping in mind you need to use a delay big enough to be able to see it flashing and a 270R resistor to anode to limit current.

Use the timer and loop cycle around for the overflow, update a memory location and check for Z bit

If location in ram is 0 for instance

movlw b'00010000'
movwf 0x00

clear timer0, set prescaler to 1/256, this gives a frequency ~63 Hz, then by dividing that by ram 0 (16) gives 4 Hz, very visible, as you use one cycle to clear the led and the next to set it then it's divided by 2 again and gives 2 Hz.

After the above commands you loop around on the timer0 interrupt, wait for it then clear the interrupt in a routine and then set the led on or off. Below is the code for 12F675 that I wrote as my first project.

        #include P12F675.INC
;******************************************************
        org     0000
        bcf     status,5        
        clrf    gpio
        movlw    b'00000111'
        movwf    cmcon
        movlw    b'00000000'
        movwf    intcon
        movlw    b'00110101'
        movwf    t1con
        bsf     status,5
        clrf    trisio
        movlw     b'00000001'
        movwf    pie1
        movlw    b'11000111'
        movwf    option_reg
        clrf    ansel
        bcf     status,5
;******************************************************
loop    movlw    b'00100000'
        btfsc     intcon,2
        xorwf    gpio
        movlw    b'00010000'
        btfsc    pir1,0
        xorwf    gpio
        bcf        pir1,0
        bcf        intcon,2
        goto     loop        
    end

Top part is setup bottom part is the timer loop XORWF will exclusive OR the led output bit. The code isn't pretty but functional, later PICs have BTG ( BiTtoGgle )

[Johan1973]

Easier said than done.. I need to learn everything from the ground up. How to make project, how to program the chip, etc.