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f6ggy
- 6th October 2003, 22:59
I does not include/understand how to place the ENB(enable) signal with the following configuration:
- function of signal ENB (enable)
http://f6ggy.dyndns.org/temp/img032.gif

-a part of the fichier.bas (pic BASIC pro) PORTA.4 = ENB
http://f6ggy.dyndns.org/temp/img033.gif

Melanie
- 7th October 2003, 09:19
Just as in the description and the example code, the ENB pin is ALWAYS kept LOW (make sure your code initialises this pin to be Low at the start), pulsing HIGH momentarily (in the code example it goes high for 100uS) after your ShiftOut statement. That's so the data that you've just shifted is actually transferred into the chip proper on completion. In the code example, PORTA.4 is obviously connected to the ENB pin. Now PORTA.4 is normally an open-drain on a PIC, but this doesn't matter because the ENB pin on your chip has an integral pull-up Resistor.

Melanie