WinPicProg Forums

[greg]

hi,

very beginner question here. i've programmed my pic16f648a with the code from tutorial 7.1, but i'm unsure of what baud rate to set my serial line at on the receiving machine.

your tutorial states the code speed is running at 9600bps, and i'm wondering if in this case the baud rate would be 9600 as well? i'm new to serial pic programming and i don't know how many bits are sent per baud using this code. 1? 2? 4?

i've tried many baud rates (300,1200,2400,etc) but keep getting gibberish on the output side.

thanks

[greg]

ok after re-reading several bps vs. baud write-ups, i'm thinking that since the pic is only capable of two voltages, that 9600bps means its also 9600 baud.

for anyone that cares or has the same question i did, the baud rate is the maximum rate at which the signal voltage could change. for a pic chip, it could theoretically change from 0 to 1 or 1 to 0 for each bit (101010101010). since it can send 9600 bits per second, that equates to a maximum possibility of 9600 changes in voltage per second. baud is changes per second, bps is total number of bits per second.

now if the pic could transmit 0, .25. .5 and 1 you could get a higher BPS rate for a lower baud rate. that is, the signal could be any one of 4 voltages at any time, so you have to multiply your baud rate by 4 to get the BPS value.

[KC]