chevymn1964
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how to connect 74hc154 to another 74hc154
Hello, I was wondering if anyone has had the same problems that I have with a PIC16F84.... It seems like port decay! Im using a PIC16F84 that is controling a 74HC154 ( intput shift register ) and a 74HC595 ( output shift register ) and the problem that I am having is with the clock pin. It seems like it would clock 8 times to "shift" the data and after about 5 or 6 re progams to work out software bugs the i/o port would start to go away. I looked at it on the scope and when I would first start there would be a nice clean square wave and after a few re progams the low side of the edge's would start to round off instead of a "clean" on-off true square wave????? any ideas? can you only re program PIC19f84's a few times???? It makes troubleshooting my software very difficult!!! lol thank you!
Hello, I was wondering if anyone has had the same problems that I have with a PIC16F84.... It seems like port decay! Im using a PIC16F84 that is controling a 74HC154 ( intput shift register ) and a 74HC595 ( output shift register ) and the problem that I am having is with the clock pin. It seems like it would clock 8 times to "shift" the data and after about 5 or 6 re progams to work out software bugs the i/o port would start to go away. I looked at it on the scope and when I would first start there would be a nice clean square wave and after a few re progams the low side of the edge's would start to round off instead of a "clean" on-off true square wave????? any ideas? can you only re program PIC19f84's a few times???? It makes troubleshooting my software very difficult!!! lol thank you!