Hi All,
This thread originated in the BAP28 forum which has split and evolved into two different problems…so I continue it here:
Another problem has appeared, the PS/2 controller (LynxMotion’s wireless version) isn’t working. On my old 465B scope --the DAT line is wiggling with poorly shaped pulses. The DAT signal looks like it is riding on a small 60 cycle AC signal (200 mV), like it doesn’t have ground reference? I double checked the wiring for the PS/2 receiver, it is correct.
I remembered reading that a pull-up resistor need be installed on Pin12/DAT line. It seemed to me that the resistor value might be a little hot for a pull-up, but I stuck it in, now the DAT line is high with no activity. SEL, CLK and CMD are present.
Ok, I pulled out the 1k pull-up and replaced with a 5.6k pull-up, now I can see spikes on the DAT line, but nothing gets to close to ground…it is still high. Without the pull-up in the (P12) circuit I see a pulse that goes to 1 volt inside the high pulse-width of the CLK on top of a 60 cycle signal, (obviously something is not right here), in that case the shiftin reads 0x00, with the pull-up installed it reads 0xFF, --pushing buttons on the PS/2 console affects nothing as far as I can determine.
On a hunch, I pulled apart the PS/2 wireless (TX side) console, and therein observed very badly soldered battery compartment connect wires…both cold-joints both ends. I unsoldered and replaced the red/black with #28 ga wire and resoldered, put it back together (struggled with the fall-out plastic button tops) and surprise, there two LEDs which now flash!!! What do these indicate? There seems to be a startup sequence, switching ON the powerswitch, first the left blinks slowly for 8 counts, and then they both blink fast for around 90 seconds and then they both stop blinking. Depressing the Select button will cause them to flash fast again. No other buttons seem to affect the LEDs. Now, after leaving the console ‘ON’ for around thirty minutes, the LEDs no longer flash regardless of state of power-switch. Leaving the powerswitch off for five minutes and now the LEDs flash when switched on.
Regarding the RX side, there are two LEDs, only one illuminates, what’s the deal with this?
Hmmmm… I am very suspiscous at this point…that both sides are dead,
TX and RX. Any suggestions?
Is there a write up somewhere on these controllers?
Thanks in advance
pirate