Serial port connection is intermittant on laptop

[ohmstable]

serial ports laptop voltage

I have a PIC project that transfers data to PC via RS232. This thing works flawlessly on my desktop PC at 57600, however on my laptop it is giving me problems. Sometimes it works ok for 20 seconds or sometimes 5 seconds then starts getting errors. Has anyone ever experienced this before?? Between the PIC and PC I've got a MAX233 RS232 Receiver/Driver. Could the serial port on the laptop be weak?

Anyone have an idea's on this issue??

 

[Antharax]

serial ports on laptops don't have full swing voltage levels.
Desktops send -12V (1) and 12V (0) if i remember correctly.
Laptops sometimes -5V and 5V or less.
But since the uart spec says that everything between -12V and -3V should be seen as 1 and everything between 3V and 12V should be seen as 0 this should not cause any problems.

But it might be the problem.

Antharax

 

[glenjoy]

serial ports on laptops don't have full swing voltage levels.
Desktops send -12V (1) and 12V (0) if i remember correctly.
Laptops sometimes -5V and 5V or less.
But since the uart spec says that everything between -12V and -3V should be seen as 1 and everything between 3V and 12V should be seen as 0 this should not cause any problems.

But it might be the problem.

Antharax

Antharax is right, and fo not push your luck on laptops' serial ports. sometimes we use programmers using a serial port and also get our programmers power from its serial port, avoid it at all costs, it can burn your laptops mobo.