Lpc2000

Hello Rui,

Ake write
>With en error less then 1% there should be no problem for CAN.
I think so too.

> Did you test your CAN settings over a large cable (500m)?
Not yet, only a few meters.

> Did you test the CAN comunication between your ARM and another
> equipment or with 2 ARM with the same settings?
At the moment I communicate with a CAN to USB Dongle and it worked perfect.

http://www.peak-system.com/db/gb/pcanusb_gb.html

Best regards,
Martin




> Hello guys and thank you very much for your fast answers.
> 
> I'm thinking in doing this.
> Use a 15MHz cristal.
> Use PLL to set cclk to 60MHz.
> Set VPDIV to define pclk to 60Mhz.
> 
> With this settings I have 0% error in defining the CAN baud rate 
> and a maximum of 1.72% error in RS-232 baud rate at 115.200.
> At 19.200 I get 0.16% error. In this group I found that RS323
> error should be less than 3% so I think I'm OK.
> 
> I think it's better to have no error in CAN than in RS-232.
> In CAN if the cable is to long I get errors due to the baud 
> rate setting and errors do to the size of the cable.
> 
> Am I right? Any comments?
> 
> Martin:
> Did you test your CAN settings over a large cable (500m)?
> Did you test the CAN comunication between your ARM and another
> equipment or with 2 ARM with the same settings?
> 
> Regards.
> Rui
> 
> 
> 
> --- In lpc2000@yahoogroups.com, "Ake Hedman, eurosource" <akhe@b...>
> wrote:
>>
>> Martin Steppuhn wrote:
>> 
>> > Hello Rui,
>> >
>> > I 'am using the LPC2129 an there ist the same "problem".
>> >
>> > You can fix it with the CAN setup by chosing a time quanta
>> > with a low error in the CANBTR.
>> >
>> > For 14,7456 MHz and 125k CAN Buadrate my settings for CANBTR are:
>> >
>> > #define   CALC_BRP_43      0x0000002A
>> > #define   CALC_SJW_1        0x00000000
>> > #define   CALC_TSEG1_8    0x00070000
>> > #define   CALC_TSEG2_2    0x00100000
>> >
>> > #define   CANBitrate125k      CALC_BRP_43 | CALC_SJW_1 |
> CALC_TSEG1_8 |
>> > CALC_TSEG2_2
>> >
>> > Error:  -0,24%
>> >
>> > You can find additional infos in:
>> > http://www.hitex.co.uk/arm/lpc2000book/index.html
>> >
>> > Best regards,
>> > Martin
>> >
>> >
>> >
>>  
>> With en error less then 1% there should be no problem for CAN.
>> 
>> Cheers
>> /Ake
>> 
>> -- 
>>  ---
>> Ake Hedman (YAP - Yet Another Programmer)
>> eurosource, Brattbergavagen 17, 820 50 LOS, Sweden
>> Phone: (46) 657 413430 Cellular: (46) 73 0533 146
>> Company home: http://www.eurosource.se      
>> Kryddor/Te/Kaffe: http://www.brattberg.com
>> Personal homepage: http://www.eurosource.se/akhe
>> Automated home: http://www.vscp.org
>>
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