16F690 MCLR as Input

[jackberg1]

Hello everyone,

a very basic question,

I have a 16F690 with the RA3 MCLR configured as input, and the RA3 pin

is connected to a 4k7 resistor pulldown and a switch tied to the VDD and it's working fine when the switch

is open I detect a low and when the switch is close I detect a high.

with the MCLRE bit #5 to = 0 the MCLR is tied to VDD

(0 = RA3/MCLR/VPP pin function is digital input, MCLR internally tied to VDD)

if the MCLR is tied to VDD, how come my pulldown + switch are working as it is.

does the MCLR has already an internal pullup resistor

if I remove the pulldown resistor with the switch open, the MCLR act as if it is high.

it need the pulldown resistor to be a low.

any suggestion ?




Also the internal EEPROM of the 16F690 is divided into 256 bytes location with address from 0 to 255
if I write 0, word B, C, does it mean the address 0 and 1 will contain the word variable B and at address 2 will contain variable C (byte)

Thanks for all comments.