Thursday, October 9, 2008

Finally got the shift registers


I got the shift registers today. After putting them away i assembled the test circuit which is listed below. My driver almost worked as it was written. I did verify that the shift register in the joystick was damaged. I then found a small bug in my driver, not really a problem with code but a problem with the concept. After looking at the data sheet a little closer i noticed that the eighth bit(H) was directly coupled to the output stage. Initially i assumed that all stages were symetrical in terms of clock relationship. 

Well, after noticing the problem i restructured the driver so that the clock pulse would occur after the data bit reading.

The driver works perfect. I need to replace the damaged shift register and fix some wires i managed to break in the process. After i get the stick assembled and verify that it still works i will be able to write some code to get this thing done.

No comments: