??? 06/13/08 14:42 Modified: 06/13/08 14:48 Read: times |
#155864 - Your schema looks fine Responding to: ???'s previous message |
However, you do not have a single decoupling cap anywhere on your board. Also, I hope you've not built your circuit on a dot board. I am assuming you are sure the RST/PSEN switches are the normally open type(Under stress, such things happen)
ps: how about checking without the processor? short the RXD and TXD pins at the CPU socket and then do the same test as before to make sure that the signals are not lost enroute to the cpu and back |