>Make sure that the reset pin is not floating. Thank you for your reply. Well I checked reset again and there is not problem with the that pin. The problem is when I send a nibble (0001-1111) to PortA too many times but the same each time , checking with the scope, I notice that the very first nibble output is right but the following are different, for example, when I try to send 0010 many times to portA, the very first output on portA is 0010, which is correct but the output following the very first one is 0001 instead. This shift from 0010 (1st. output) to 0001(subsequent outputs) is seen like a flickering at the beginning of output on portA. > > > >---"Gerhard Fiedler (by way of \"Eduardo R.\" >)" wrote: >> >> Hi everybody, I need your help one more time. >> >> I am using PIC 16F84 PortA as an output and sending a nibble (0001 >- 1111) >> everytime an output signal is required. The program works fine but the >> circuit is not giving a clean output. Some bits that should remain >Low are >> flickering once instead (47.2ms pulse ). >> I have noticed that it happens in the closest bit to the activated >output >> bit. The bit which flickes is different according to the output >nibble but >> is always adjacent to an activated (Hi)output bit. >> >> Everything looks perfect when is simulated on MPLAB >> >> Any help will be greatly appreciated. >> >> >> Best wishes >> Eduardo R >> >> AC Power Control project based on PIC >> http://www.geocities.com/SouthBeach/Cove/4535 >> ICQ# 10909825 >> erivera@umemphis.campus.mci.net >> >> CHILDHOOD CANCER >> "Anyone whose family hasn't been touched by it >> should get down on his knees every night and >> thank the MAN upstairs"...........SAM COOPER >> > >_________________________________________________________ >DO YOU YAHOO!? >Get your free @yahoo.com address at http://mail.yahoo.com > > Best wishes Eduardo R AC Power Control project based on PIC http://www.geocities.com/SouthBeach/Cove/4535 ICQ# 10909825 erivera@umemphis.campus.mci.net CHILDHOOD CANCER "Anyone whose family hasn't been touched by it should get down on his knees every night and thank the MAN upstairs"...........SAM COOPER