Help with pic16f690 -max232cpe

[krise86]

Can you post the schematic?

Al.

[aratti]

Something doesn't work with your wiring:

Max232 pin 10 should be connected to pic 16F690 pin 10 (RB7 Tx)

Max232 pin 9 should be connected to pic 16F690 pin 12 (RB5 Rx)

Connect a decoupling capacitor 10nF from Vdd to Vss on pic power pins.

Al.

[krise86]

Well it is connected that way pin 10 -> rb7 and pin9 -> rb5

The 16f690 was not in the schematics program but that how i connected it.

but im reading -10v on rs232 pin 3 and 5 is that right?

I dont have a 0,01uf can i use 0,1uf?
wait i think it's on the demo board

[aratti]

but im reading -10v on rs232 pin 3 and 5 is that right?

Yes! Max232 is a voltage level translator.

I dont have a 0,01uf can i use 0,1uf?

Yes!

Al.

[krise86]

Yes! Max232 is a voltage level translator.



Yes!

Al.

That did nothing, is there a way to check if the signal is coming out from pin 9 on max232?

[aratti]

That did nothing, is there a way to check if the signal is coming out from pin 9 on max232?

Yes place a led with 1K in series from pin 9 to gnd.

But, I am more interested on how many IO pins you are using. Now If you have inputs pins floating (not connected) this can produce wierd result.

I noted in your code, that you are not setting the tris registers, please do it. Set all non used pins as output and place them to a logic zero.

Example (I assume you are using only the serial pins) :

TrisA = %00000000
PortA = 0

TrisB = %00100000 ' if the only input is pin 10 Rx
PortB = 0

TrisC = %00000000 ' if none of the portC pins are used
PortC = 0

The above code has to be written on top of your code. It will set all non used port as outputs @ logic zero, avoiding to leave inputs floating.

If your arrangement is different modify the tris command to suite your need.

Al.

[krise86]

Yes place a led with 1K in series from pin 9 to gnd.

But, I am more interested on how many IO pins you are using. Now If you have inputs pins floating (not connected) this can produce wierd result.

I noted in your code, that you are not setting the tris registers, please do it. Set all non used pins as output and place them to a logic zero.

Example (I assume you are using only the serial pins) :

TrisA = %00000000
PortA = 0

TrisB = %00100000 ' if the only input is pin 10 Rx
PortB = 0

TrisC = %00000000 ' if none of the portC pins are used
PortC = 0

The above code has to be written on top of your code. It will set all non used port as outputs @ logic zero, avoiding to leave inputs floating.

If your arrangement is different modify the tris command to suite your need.

Al.

I did that now but still nothing usful, it seems that the data is coming out from the max but it wont register at all i do get something when i send like 200 times with 10ms