One last remark, the memory chip IC21 is not included in the memory test, this is impossible, as the data is being written through the databus, but reading does not happen through here. It was necessary to test the inputs, as this board does not use PIA's for in- and output. We shall connect the input pins at connectors CN9 ( there are 8) one by one to ground, and every time the cpu stops blinking and goes " out", at the moment we release the input pin the LED restarts blinking. Meanwhile a "control LED" is blinking rapidly. If both memory chips are ok, the test will automatically continue the "input test". If something is wrong then the test will continue to run the memory test. ![]() At startup all outputs will go up and down in rhythm, between 5 and 0 volt. You should visit his site, as a lot of technical information about Zaccaria is collected there, and it was the only website on which I found some technical information. David tried out this repair method and reported positive results and made several corrections for the English translation. ![]() First generation, Earth Wind and Fire, Hot Wheels, Future World, House of Diamonds, Winter Sports, Shooting the Rapids, Fire Mountain, Space Shuttle, Star God, Locomotion.
0 Comments
Leave a Reply. |