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Discussion Starter · #1 ·
as it says on the tin really?

are people using the default 9600 baud? or can performance be enhanced with a faster baud rate?

Maby its in the distructions somwhere and i just missed it.....
 

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Pit pro uses 4300 Baud rate. I know this from measurment, and i've built my own pit sensing system. Havn't measured the C7042 to PC baud so can't comment on that

Matt
 

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Hi Mark ........


High ..... as in 115200. The APB will not communicate at this rate but the port can negotiate down if needs be ..... it won't go higher. The 9600 rate is a default by MS and they have never seen fit to up this, I guess because most people vary rarely use this kind of serial port any more.

When Windows came along on the PC, COM 1 was always assigned to the mouse and 9600 was fine for that purpose.
 

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QUOTE (mpg200 @ 4 Jul 2012, 11:35) <{POST_SNAPBACK}>Pit pro uses 4300 Baud rate. I know this from measurment, and i've built my own pit sensing system. Havn't measured the C7042 to PC baud so can't comment on that

Pit-Pro communicates at 38K4 Baud, this is the same rate as the original C7030 Powerbase. C7042 communicates at 19K2 Baud. These are fixed and cannot be changed, there is no negotiation. However unless you are writing an RMS there is no need to worry about this info as the Race Management Programs will select the correct baud rates.

Rich
 

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We must be in the land of tolerance then, as I definitly measured the output signal from the FTDi usb cable connected to SSDC on the pit pro port did the maths and arrived at 43K which i thought was a little odd but went with it. Then calulated the approriate baud rate generator for my chosen pic to run at 43K (or as close as I could get) and I get SSDC to respond to my pit lane system. I'll check my code to see axactly what I set it to and measure my output to see if I'm just on the edge of working within the tolerances.

Edit: also
looks like missed 0, I mean 43000 not 4300, thats a big mistake in the land of comms
 

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Discussion Starter · #9 ·
ah right cheers lads

@Rich: I hadnt realised windows programs could coontrol the baud rate, I thought it was locked to whatever was set by the driver - or less than..

guess the best thing i could do there is just leave it alone then ;-)
 

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OK 43K makes more sense and is probably within the tolerance for 38K4, particularily with the propper serial interface there is in a PIC or PC. For Pit-Pro there was no serial interface in the PIC chip the PLG uses so it's "bit bashed" in the assembly code, and not that tolerant of timing errors.

Rich
 

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Ok done some calcs,
my PIC based sensing circuit is chucking out packets at 43K1 and SSDC responds correctly, I dont bother reponding to the light information that SSDC sends to pit pro, I have no lights. I'm measuring the PIC USART output before it gets processed by the FDTi interface. so it appears to be quite forgiving. I will however tweek my code to get 38K4 and see what happens.
Mark I recon you should get tinkering, the more brains the better, provided they dont miss out 0000s Doh
 

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@Rich
Ahh 'bit bashing' I stayed away from that as too much hassle, been there before with bit bashing PWM for an LED driver. I used a 16F628 for my pit sensing.
 
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