Many have her stated that i am rude in my expressions above.

NO WAY

Do I, who do understand the ports, have a personal interest in this - no. Have I seen, again and again, otherwise capable people running around in circles trying to figure out "input mode" and output mode" - yes.

Have I tried "gently" in the past to make it clear how confusing these expression are - yes, did it do any good - no.

When this urban legend is popping up every month and confusing every novice that, instead of having "quasi-bidirectional" explained is made totally crazy by trying to understand "input mode" and output mode", it is not productive.


just see the original post.

To make all the lines of this port as High, can I give the instruction:
P1 = 0xff;
Will it not make the port P1 as input port?

In the "mode system of description" the answer is an unconditional yes, but answering "yes it makes the port an input port" would make it impossible for the OP to ever find out how to output a '1'


If the expressions "input mode" and "output mode" could be eradicated and quasi-bidirectional could be the norm, maybe some would make a bit of progress, instead of spending hours trying to "output in input mode".

Just to show how ridiculous the "input mode" and output mode" expressions are, read the following, which is totally correct when adhering to the mode baloney:
"to input to a port you have to write a '1' to it in output mode"
Crystal clear isn't it.

Instead:
"When a port is set to a '1', it is possible for an outside signal to pull it low."

Which of the above can anybody understand without raking their brain???

quoting "the bible" :
for Ports 1, 2, and 3, the pin is pulled high by a weak internal pullup, and can be pulled low by an external source.

That one of the posts above seems to go one step further and mis readin port pin vs reading port latch in with input mode" and output mode" just show how totally confusing the terminology is.

Erik