Im making a new Proto board for a 16f628 and 16f877, are there any problems using 16f628's portA for 4 bit LCD output ? other than turning on Digital.
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Im making a new Proto board for a 16f628 and 16f877, are there any problems using 16f628's portA for 4 bit LCD output ? other than turning on Digital.
Hi,
On the 628 RA4 is open drain so it can't actively drive the output high, only pull it low. A pullup resistor is needed to be able to get a logic '1' on that pin. RA5 doesn't have any output drivers at all so it's input only.
/Henrik.
HenrikOlsson
Thanks for your reply RA5 I did not bring out from the 16f628 to the header so ok there and RA4 is used as RS and pulled high with resistor and using A0 ~ A3 and my 4 data bits looks like Im ok
thank you for the reply
Larry