RS232 comm

[Darrel Taylor]

At 48Mhz ... You have to use the 16-bit baud rate generator to get 2400 baud. It's too slow for the normal BRG.

Try it like this

DEFINE HSER_RCSTA 90h ' Enable serial port & continuous receive
DEFINE HSER_TXSTA 20h ' Enable transmit, BRGH = 0
DEFINE HSER_CLROERR 1 ' Clear overflow automatically
DEFINE HSER_SPBRG 225 ' 2400 Baud @ 48MHz, 0.0%
SPBRGH = 4
BAUDCON.3 = 1 ' Enable 16 bit baudrate generator

Or for other baud rates, use mister-e's calculator (EUSART calc)...

PicMultiCalc V_1.3.1
http://www.picbasic.co.uk/forum/atta...achmentid=2957

[longdw]

I tried mister e (handy tool).

I now send a "D" and receive a 0.

Tried pumping it up to 9600 baud and many other things but it is always a 0 or doesn't work at all.

If I go back and try serialcom.exe from PC to try & get something to work right, would I use a straight cable instead of a null modem cable ?

Thanks Darrel

[EarlyBird2]

RS232 has two equipment types Data Terminal Equipment (DTE) and Data Connect Equipment (DCE). Your computer is a DTE and has a male connector as all DTE equipment has, that is if the RS232 standard has been followed. All equipment intended to connect to a computer RS232 port is DCE and has a female connector. In the early days null modems were intended to be used to connect two computers and therefore a null modem cable was female to female. This was before networks were invented. The problem now is that we have DCE to DCE equipment which requires a male to male connector, which are hard to find and easy to make. So if the two pieces of equipment have the same gender a null modem is required, RX and TX are crossed. If one is male and the other female then a straight serial cable is needed.

Unless of course you have a piece of equipment that has not followed the RS232 convention and there are some trust me.

Clear as mud?

Steve

[dhouston]

It's not clear to me what you have at each end of the RS232 link. Are you trying to communicate from a PIC to a PC or to another embedded device?

The hardware UART output is non-inverted while a PC expects it inverted and most embedded devices expect it non-inverted.

[longdw]

Problem solved.
Went back to serialcom.exe and got PC talking to Labxusb and then to labx1 after making suggested chgs.

Now labxusb and labx1 are talking fine.

Thanks all!!!!!

Darrel Now that that's working hopefully OSU will not get blown out by USC !!

[Darrel Taylor]

Great!
Glad you got it working.

I'm originally from Columbus, and now live in California.
So I'm quite sure ... and my bet would be for ... Not OSU.

[Darrel Taylor]

So I'm quite sure ... and my bet would be for ... Not OSU.

OUCH!
And I gave up 10 points.

USC-18    OSU-15

%$#@!& College Football
Definitely not a Blow Out.