rs232

[rondo2]

Also

i measured the voltage on the pin which transmits the serial data fron the gps module, and it was only 1.5v, now is that normal.

the pic micro will not see the data at such low levels will it ?

[Archangel]

i'm using a 16F870 will it accept voltages as low as 3.3v on an I/O pin

Data Sheet: "Wide operating range 2.0 to 5.5v . . . " I would make my own headaches small and run the
pic and gps on 3.3v, 1 supply 1 headache 2 supplies 2 . . .

Also

i measured the voltage on the pin which transmits the serial data fron the gps module, and it was only 1.5v, now is that normal.

the pic micro will not see the data at such low levels will it ?

3 ways to get fish, buy fish, learn to fish, beg fish at the dock ... to learn to fish you have to observe others
even if their fishing is not what you want today. I mean by this, read posts that do not apply to what you are doing today <br>
Look at the GPS data sheet, it's pretty thin I admit. Your GPS unit communicates @ 9600 b True, which means it is
"active low" as stated in the data sheet. This means it does not supply +5 or +3.3 on that port. Where does it get it? From the
pullup resistor, you are going to put on that line to the 3.3v supply. True requires a pullup whereas Inverted
would like to idle low with a pulldown.

hi thanks for pointing that out but still nothing.

i changed my code to serin2 TX,<font color = red>84</font color>,[WAIT("$GPGGA"),WAIT(","),DEC2 H,DEC2 M,DEC2 S]


PAUSE 200

HIGH PORTC.0
PAUSE 200
LOW PORTC.0
PAUSE 200

SEROUT2 PORTC.1,16468,[dec2 H, dec2 M, dec2 S]

GOTO MAIN

84 sets serin2 to Driven true 32852 sets it to open true. Try the open true setting

@ device  pic16f870,BOD_on

turn this OFF until everything else works and turn on PWRTE ON, it just gives the power supply a little time to stabalise before the PIC boots

@ device  pic16f870,XT_OSC             'Using External Oscillator

I honestly do not if this will cause problems given your 20 mhz define, since you are using an external OSC, but why chance it ?
I would make it HS, might not change anything, except you will know for sure that is NOT a problem.

[rondo2]

Data Sheet: "Wide operating range 2.0 to 5.5v . . . " I would make my own headaches small and run the
pic and gps on 3.3v, 1 supply 1 headache 2 supplies 2 . . .



3 ways to get fish, buy fish, learn to fish, beg fish at the dock ... to learn to fish you have to observe others
even if their fishing is not what you want today. I mean by this, read posts that do not apply to what you are doing today <br>
Look at the GPS data sheet, it's pretty thin I admit. Your GPS unit communicates @ 9600 b True, which means it is
"active low" as stated in the data sheet. This means it does not supply +5 or +3.3 on that port. Where does it get it? From the
pullup resistor, you are going to put on that line to the 3.3v supply. True requires a pullup whereas Inverted
would like to idle low with a pulldown.


84 sets serin2 to Driven true 32852 sets it to open true. Try the open true setting

@ device  pic16f870,BOD_on

turn this OFF until everything else works and turn on PWRTE ON, it just gives the power supply a little time to stabalise before the PIC boots

@ device  pic16f870,XT_OSC             'Using External Oscillator

I honestly do not if this will cause problems given your 20 mhz define, since you are using an external OSC, but why chance it ?
I would make it HS, might not change anything, except you will know for sure that is NOT a problem.

HI Joe,

the open true serial settings fixed it

thanks a lot