Good evening.
I would like to know what is the waveform on pin 9 of the 556. I am using my oscilloscope but no any waveform was detected. The main issue is tha the screen is showing rubbish but before to replace the main IC.
Thanks in advance
I would look at U1 pin 2. It should be zero for a few moments at power up then go to 5v and stay there. It’s function is to reset the screeen controller and get ready for work. So the input of that will be opposite, should be high for a few moments at power up and go low. I would check U1 first.
Thanks, I will check it.
Thanks for the help, is as you described it. Do you know if there is another way except email to get in touch with buchty.net ?