LPC MicrocontrollersのトピックRe: CAN and RAM offset

CAN and RAM offset

lpcware — Wed, 15 Jun 2016 17:04:10 GMT

Content originally posted in LPCWare by miccio on Wed Mar 16 07:16:13 MST 2016
Hello everyone,

As far as i know, the CAN implementation on the lpc15xx is the same as lpc11Cxx.
However, I remember that some RAM offset had to be set on the latter, since the first few bytes were used by the ROM APIs.
Is it still the case on the LPC1549?

Bonus question (may grant a beer in selected countries :) )
Does the algorithm for calculating the baudrate setting which was present on the lpc11c24 example still applies to the lpc15's? If so, why has it been removed?

Thanks in advance!!

Re: CAN and RAM offset

lpcware — Wed, 15 Jun 2016 17:04:10 GMT

Content originally posted in LPCWare by R2D2 on Wed Mar 16 09:35:28 MST 2016

Quote: miccio
However, I remember that some RAM offset had to be set on the latter, since the first few bytes were used by the ROM APIs. Is it still the case on the LPC1549?

No :)

Quote: miccio

Beer question :)
Does the algorithm for calculating the baudrate setting which was present on the lpc11c24 example still applies to the lpc15's? If so, why has it been removed?

Because it wasn't very good...

And as shown in my sample:

https://www.lpcware.com/content/forum/working-lpc15xx-lqfp48-can-sample

it's easier to use a simple table :)

Re: CAN and RAM offset

lpcware — Wed, 15 Jun 2016 17:04:11 GMT

Content originally posted in LPCWare by miccio on Thu Mar 17 07:20:49 MST 2016
Hi R2D2, and thanks for the expedited answers!!

Quote: R2D2

No

That's great!

Quote: R2D2

Because it wasn't very good...
And as shown in my sample:
https://www.lpcware.com/content/forum/working-lpc15xx-lqfp48-can-sample
it's easier to use a simple table

You're right about using a simple table - after all, I guess I will rarely need to set the baudrate to some arbitrary value.

Time for a new question now: is there a more verbose description of the error status bits for CAN? couldn't find any in neither the LPCOpen library nor the UM.
Is it just me or this is not very self-descriptive?

#define CAN_ERROR_NONE0x00000000UL
#define CAN_ERROR_PASS0x00000001UL
#define CAN_ERROR_WARN0x00000002UL
#define CAN_ERROR_BOFF0x00000004UL
#define CAN_ERROR_STUF0x00000008UL
#define CAN_ERROR_FORM0x00000010UL
#define CAN_ERROR_ACK0x00000020UL
#define CAN_ERROR_BIT10x00000040UL
#define CAN_ERROR_BIT00x00000080UL
#define CAN_ERROR_CRC0x00000100UL

Re: CAN and RAM offset

lpcware — Wed, 15 Jun 2016 17:04:12 GMT

Content originally posted in LPCWare by R2D2 on Thu Mar 17 07:53:53 MST 2016

Quote: miccio
Time for a new question now: is there a more verbose description of the error status bits for CAN? couldn't find any in neither the LPCOpen library nor the UM.
Is it just me or this is not very self-descriptive?

#define CAN_ERROR_NONE0x00000000UL
#define CAN_ERROR_PASS0x00000001UL
#define CAN_ERROR_WARN0x00000002UL
#define CAN_ERROR_BOFF0x00000004UL
#define CAN_ERROR_STUF0x00000008UL
#define CAN_ERROR_FORM0x00000010UL
#define CAN_ERROR_ACK0x00000020UL
#define CAN_ERROR_BIT10x00000040UL
#define CAN_ERROR_BIT00x00000080UL
#define CAN_ERROR_CRC0x00000100UL

Is this a normal or a beer question :quest:

A lot of this errors are of course CAN errors as described in CAN specs:

http://www.kvaser.com/software/7330130980914/V1/can2spec.pdf

Re: CAN and RAM offset

lpcware — Wed, 15 Jun 2016 17:04:12 GMT

Content originally posted in LPCWare by miccio on Thu Mar 17 08:18:43 MST 2016

Quote: R2D2

Is this a normal or a beer question :quest:

Could be a beer question too, depends on where in Germany you live!
I'm going to visit Fulda, Regensburg, and maybe Nuremberg in two weeks.
So maybe it's time to redeem those beers! ;-)

Re: CAN and RAM offset

lpcware — Sun, 19 Jun 2016 01:05:21 GMT

bump