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need help with my Betson Imperial trackball
PL1:
--- Quote from: Zkam on June 29, 2024, 04:47:20 pm ---I would like to Replace the USB cable and use that for the trackball inputs.
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Good to see in that last photo that you have the 4-pin jumper for J3/J4. ;D
Those rollers look rather badly worn.
- Once you get the trackball confirmed working, you may want to look for replacements for the rollers and maybe the bearings, too.
The mouse button connector has a 5v pin instead of a ground pin.
- That indicates that this is an older-style "active high" circuit, not an "active low" circuit like the MiniPac.
I'll work on the details for J4 wiring so you don't get that one backwards.
Hopefully a USB to Dupont cable like this one or this one will work on J2 using the pinout info here.
- If you like, you could use the 1x4 Dupont housing from the cut PS/2 cable in place of the four 1x1 housings that come with those USB cables.
Scott
PL1:
. . . and here's the pinout for the J3 to J4 jumper. :cheers:
Scott
Zkam:
Hi. The USB-to-Dupont cable came in today. I connect it to the J2 pins in this order: red to 5 volts, white to clock, green to data, and black to ground. I connected the USB to the laptop and still did not get the cursor to respond. Is there something else I need to do? Thanks for your help.
PL1:
--- Quote from: Zkam on July 02, 2024, 01:46:54 am ---red to 5 volts, white to clock, green to data, and black to ground.
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Close. White is data and green is clock -- J2 wire color order should be red, green, white, black.
If that doesn't fix it, verify that the USB pins ==> wire colors are correct using your multimeter and that pinout page.
- It's not likely to be wrong, but it happened on a cheap USB cable that someone on BYOAC hacked a while back.
Use a digital camera to see if the opto IR LEDs are working.
- If the LED on both optos of an axis are dead, there will be no cursor motion.
- If one of the two optos has a dead LED, the cursor will wobble back and forth one step when you move the encoder wheel for that axis. For example, if line A is always low due to a burned out LED, line B alternating high and low will wobble between phases 1 and 2.
If all of the above look good, you may need pullup resistors for the clock and data lines as mentioned on the pinout page.
--- Quote ---It's good practice to pull up data/clock lines with some resistors of 10k or so. Especially when connecting to newer motherboards. In some cases signal has levels between 1.5 and 2.5 volts, and mouse don't work. Pulling up helps in that situations and doesn't harm if unnecessary.
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This post discusses PS/2 to USB converter pullup resistors connected to 3.3v.
https://retrocomputing.stackexchange.com/questions/28298/how-did-an-old-mouse-detect-if-it-was-connected-to-ps-2-or-usb-port
--- Quote ---@PeterMortensen Which is why these Holtek MCUs are a bit special and have stronger internal pull-up on the specific pins that are shared with PS/2 and USB. PS/2 data has nominally 4.7k internal and PS/2 clock needs the external 1.5k anyway for USB.
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Scott
Zkam:
Hi. I belief the LED on both optos are dead. I could not see anything, even with the digital camera. I found a set of Wico Trackball Opto Boards.
They fit perfectly in the case. Will these work as well?