12 | | After spending several hours the main schematics of those button boards has been decoded. Here is an image, I created with EAGLE, showing how those both PCB works. |
13 | | '''Note''': The both encoders showed on the image, do not show the original connecting, but the way, how I changed it in order to easy access them. So recheck this first, if you like to build same thing!!! |
| 12 | After spending several hours the main schematics of those button boards has been decoded. Here is an image, I've created with EAGLE, showing how those both PCB works. |
| 13 | All the status LEDs resistors are 80Ohm, so I assume they were driven originally with around 3,3V. The background LEDs seems to be driven with 12V pwm modulated signal, however not sure for now. On the E39-forum.de somebody found out the manufacturer of compatible rotating knobs for the 4:3 monitor. I think for |
| 14 | the 16:9 it could be the same. The original knobs where a special development for Alpina. The compatible one is that one: Grayhill 61C22-01-04-02, [http://datasheet.octopart.com/61C22-01-04-02-Grayhill-datasheet-67218.pdf data sheet]. |
| 15 | |
| 16 | '''Note''': The both encoders showed on the image, do not show the original connecting, but the way, how I changed it in order to easy access them with an uC. So recheck this first, if you like to build same thing!!! |