Lpc2000

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
>