8-bit Microcontrollers中的主题 Re: Baud rate error with Processor Expert

Baud rate error with Processor Expert

ecotecsa — Thu, 08 Apr 2010 22:14:22 GMT

Hi, setting up baud rate with (Processor expert ) Asynchroserial bean , when test with oscilloscope, baud rate is -20% as expected .

Obviously , don´t communicate . Any ideas?.... Thank you.

JM60 , 12Mhz crystal.

Re: Baud rate error with Processor Expert

ProcessorExpert — Thu, 08 Apr 2010 22:47:52 GMT

Hello,

this kind of issues is in most cases caused by inccorect value of crystal/oscillator in CPU bean. Hence could you please check that value of crystal on your PCB (12 MHz) is properly set in CPU bean in your project?

Otherwise in case that your problem will persist could you please post here a simple project to reproduced it?

best regards
Vojtech Filip
Processor Expert Support Team

Re: Baud rate error with Processor Expert

ecotecsa — Fri, 09 Apr 2010 02:28:09 GMT

Dear Vojtech

Problem persist. I have attached litle proyect and 2 jpg.

Thank you , Eduardo.

Re: Baud rate error with Processor Expert

ecotecsa — Fri, 09 Apr 2010 02:30:40 GMT

Sorry, 2 more attach.

Re: Baud rate error with Processor Expert

ProcessorExpert — Fri, 09 Apr 2010 19:49:59 GMT

Hello,

I have checked your screenshots and I think that the problem is in "High speed clock" property in CPU bean where is still selected "Internal Clock", hence Asynchroserial beans runs from this clock source even you have enabled external crystal. To avoid the problem should help switch this property to "External Clock".

However, frequency set within Asynchroserial bean should match to freqency measured on HW even you are running from internal clock. The problem in this case could be caused by incorrect trimming of internal crystal to 31.25 kHz.

best regards
Vojtech Filip
Processor Expert Support Team

Re: Baud rate error with Processor Expert

ecotecsa — Mon, 12 Apr 2010 19:45:05 GMT

Hello Vojtech

After hours of work on my custom development board , seting up Processor Expert CPU bean with external cristal 12 Mhz, and external reference (PE say 8Mhz ) ,SCI bean at 9600 bds. I have found (with oscilloscope) that BusClock is 6Mhz and Baud Rate 7200 bds . Communication is perfect but at 7200 bds.(Dockligth).

Other Baud Rates was posible with SCIxBD =(BusClk/(16*BR)).

Thank you very much.

Eduardo.

Re: Baud rate error with Processor Expert

ecotecsa — Tue, 13 Apr 2010 00:58:21 GMT

Problem solved with this PE setup , see attach.

Best regars.

Eduardo.

Re: Baud rate error with Processor Expert

Geoff_L — Thu, 18 Nov 2010 07:58:13 GMT

I'm having a similar problem, but in my case, the baud rate is only wrong if I flash program the board, and reset power. Using the debugger, and reseting power I have no baud rate issues. I'm using MC9S08AC48CPU, processor expert, and th eclipse version of the codewarrrior development studio (1.0.0) Any ideas what could be causing this behavior? I have set the PE parameter indicating that the trim value should programmed - but I can't see it actually doing while programming, like I can see with the debugger.

Re: Baud rate error with Processor Expert

Geoff_L — Thu, 18 Nov 2010 08:23:08 GMT

fl::target -lc "ShoulderFirmware_MC9S08AC48_PnE USB BDM"

fl::target -b 0x80 0x7f0

fl::target -v off -l off -ie on -i "" -p MC9S08AC48

cmdwin::fl::device -d "MC9S08AC48_FLASH" -o "FLASH" -a 0x4000 0xffff

cmdwin::fl::image -f "C:\\Documents and Settings\\glansberry\\My Documents\\SVN_EE\\Advanced_Development\\HIR\\P1\\ShoulderFirmware\\MC9S08AC48\\ShoulderFirmware.abs" -t "Auto Detect" -re off -oe off

cmdwin::fl::erase image

Beginning Operation ...

-------------------------

Initializing remote connection ...

Performing target initialization ...

Flash operation ...

Detect Speed ...

Detect Speed Succeeded. 4.313

Status Checking ....

Status Checking Succeeded. MC9S08AC48_FLASH Programmed

Erasing ....

Status Checking Succeeded. MC9S08AC48_FLASH Blank

Erase Command Succeeded.

Flash operation done

cmdwin::fl::write

Beginning Operation ...

-------------------------

Flash operation ...

Status Checking ....

Status Checking Succeeded. MC9S08AC48_FLASH Blank

Programming ...................................................................................................................................

Programming ......................................................................................................................

...

Programming ...............................................................................................................................................................................................................

Program Command Succeeded

Status Checking ....

Status Checking Succeeded. MC9S08AC48_FLASH Programmed

Flash operation done