Serial Communication with PIC16F877A

[mackrackit]

Can you post your schematic and/or a picture of your setup. I think it is down to a hardware problem now.

Caps on the 232?
Cable is straight through?
Usb to serial converter?
Real serial port?
Port on PC is known to be good?

Hold one hand in the air while touching you big toe?

Could be anything now.

[mcbeasleyjr]

Can you post your schematic and/or a picture of your setup. I think it is down to a hardware problem now.

Caps on the 232?
Cable is straight through?
Usb to serial converter?
Real serial port?
Port on PC is known to be good?

Hold one hand in the air while touching you big toe?

Could be anything now.

Well... you'd have to give me a while to get a schematic drawn up. There are 4 caps on the 232. The cable is a regular serial cable, male on one end female on the other. I don't have a USB to serial converter although using that while trying to debug does work. It is a serial port on the back of my computer so I'm assuming that it is a real port. This is first time I've really tried using the serial port so as far as knowing whether its good or not I don't know, nor do I know how to check. Device manager does say that device is working properly with no problems. Lol, and not sure I want to try that one or not. Probably fall flat on my face.

[mackrackit]

Make sure the cable is not for a modem. Pin 2 on one end goes to Pin 2 on the other, the same for pin 3.

Test PC serial port by jumping PINs 2 and 3 with a 10K and use a terminal to see if you get an echo.

[mcbeasleyjr]

Make sure the cable is not for a modem. Pin 2 on one end goes to Pin 2 on the other, the same for pin 3.

Test PC serial port by jumping PINs 2 and 3 with a 10K and use a terminal to see if you get an echo.

I tested my serial port and sent 5 succesfully in the loopback... what else can i try?

[mcbeasleyjr]

I am attaching a bitmap of my schematic for my ICD and ICP. I am using the ICD for the serial communication.

[Archangel]

Make sure the cable is not for a modem. Pin 2 on one end goes to Pin 2 on the other, the same for pin 3.

Did you test as Mackrackit suggested above? Many serial appearing cables are actually laplink cables, or nul modem cables and the Tx and Rx pins are crossed so two computers can be linked directly.

[mcbeasleyjr]

Did you test as Mackrackit suggested above? Many serial appearing cables are actually laplink cables, or nul modem cables and the Tx and Rx pins are crossed so two computers can be linked directly.

Yes I tested it... I successfully sent a message through my cable and echoed it back by shorting pin 2 to pin 3.... any other ideas?

Added:

Is there anyway to tell if my cable is crossed as you suggest?... I know I got the echo by shorting pin 2 to pin 3 but I would still get the echo if the pins were crossed...

Resolved:

Thank you guys for your help. After testing my cable for continuity I realized that it is crossed. Going to get a new cable and hopefully that fixes the problem.

[mackrackit]

Just reverse the connection at the device end, swap pins 2 and 3.
Or cut the cable...

[Archangel]

Just reverse the connection at the device end, swap pins 2 and 3.
Or cut the cable...

Or if you have a null modem adapter use it to swap back . . .