TMS570LS3137: CAN BUS configuration for baud rate

Hi Fabio,

I don't know exact root cause for the issue and CAN should work up to 1Mbps.

Jus try to refer below two threads:

(2) TMS570LC4357: API to change the CAN bit rate in Halcogen generated drivers - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

(2) RM57L843: DCAN Timing Configuration - 20Kbit/s - Arm-based microcontrollers forum - Arm-based microcontrollers - TI E2E support forums

If they don't help, then please share your project for verification and debug at my end.

--
Thanks & regards,
Jagadish.

Hi Jagadish

I'm still not able to do that :-(

I analyse the can traffic with IXXAT and when I configure my board with 125kbps (and also IXXAT) I see the correct packets but when I try to configure bot with 250kbps I see only packets but with error.

I tried with another microcontroller and I'm able so the IXXAT configuration for 250kbps is ok.

I configure and start the CAN BUS on TMS570 with two functions .... I'm going to send them with pm for security problem about the software.

Thanks in advance

FAbio

Hi Fabio,

Apologies for the delay in my response.

Can i get a simplest project for debugging at my end?

--
Thanks & Regards,
Jagadish.

Hi

I senti you a private message

Thanks

Hi 

Thanks for the code, i will look into it and will provide my update soon.

Thanks

Hi Fabio,

My sincere apologies for the delay in my response. I was on leave for last week and so many threads i had gone through. I will work on your thread tomorrow and will give my update.

--
Thanks & regards,
Jagadish.

Hi Jagadish

don't worry :-)

Many thans

Fabio

Hi Fabio,

Fabio Poiati said:

I tried with another microcontroller and I'm able so the IXXAT configuration for 250kbps is ok.

Sorry, this was not clear,
Are you able to work properly with another controller at same baudrate of 250kbps?

--
Thanks & regards,
Jagadish.

yes, just to confirm the can bus analyzer is correctly configured

Fabio Poiati said:

yes, just to confirm the can bus analyzer is correctly configured

Here another controller means not TI's TMS570?

STM570 from ST ... not TI

Hi Jagadish

sorry for my late feedback

Thanks for your analisys.

Unfortunately I-m not using HAL CODE GEN but an old projects for my previous collegue ..

Is it possible to have you canInit procedure and also CanTransmit just to verify my can managing procedures_

Thanks

Fabio

Hi Fabio,

Here are the code changes for 125kbps and 250kpbs

The left side one is 125kps and right side one is 250kbps baudrates. 

It is not just changing the BRP value for baudrate change, HALCoGen also doing several other timing parameters. Try to do the same changes and do the test on your side.

For this changes sample points are 

125kbps - 62.5%

250kbps - 66.6%

--
Thanks & Regards,
Jagadish.

I'm using PLL1 180MHz with

BRP reg =  ( 1 ) << 16 |

                   (3-1) << 12 |

                   (3+1 -1) << 8 |

                    (3 -1)  << 6 |

                     (25) << 0

and works at 125kbps baud rate

Fow which PLL1 are your configurations?

Hi Fabio,

CAN module will not use PLL1 clock directly right?

It will use the VLCK1 like as shown below:

And this will get generated as follow from PLL1:

In my case PLL1 clock is 300Mhz but the clock to the CAN module that is VCLK1 is 75Mhz.

--
Thanks & Regards,
Jagadish.

Sorry but I'm not very expert like you :-(

I'm working with the configuratons written above and they are working with 125kbps od baud rate. The comments around the can configurations tell me  that PLL1 drive the CAN and is 180MHZ

Other than BRT, which other registerns you need just to have the confirm for CAN BUS is using 180MHZ of clock?

In addiction ,,, I was trying to change the BTR and other registers during the debug phase with microcontroller suspended ... but the I was not able to change the register value ....

In addiction, can you share your code?

Hi Fabio,

Fabio Poiati said:

In addiction, can you share your code?

Sure.

Here is my code:

3301.CAN_TEST_POLL_LC4357.zip

--
Thanks & regards,
Jagadish.

thanks

I will work on it :-)

Fabio

Hi Jagadish

unfortunately my project is coming from an old application constructed with HALCOGEN but the HALCOGEN project is lost.

But I tried to use HALCOGEN with a new project wih my configuration of CAN BUS for PLL1 180MHZ and I generated 

the configuration con CAN BUS.

For 125kbps the values are the same but for other rates are different from the values used in my project.

These are the right configuration that I'm using now and with the relative rates working!

/* 125kbps canREG1->BTR = (uint32)((uint32)1U << 16U) |
(uint32)((uint32)(3U - 1U) << 12U) |
(uint32)((uint32)((3U + 1U) - 1U) << 8U) |
(uint32)((uint32)(3U - 1U) << 6U) |
(uint32)25U; */

/* 250kbps canREG1->BTR = (uint32)((uint32)0U << 16U) |
(uint32)((uint32)(4U - 1U) << 12U) |
(uint32)((uint32)((3U + 4U) - 1U) << 8U) |
(uint32)((uint32)(4U - 1U) << 6U) |
(uint32)29U; */
/* 500kbps
canREG1->BTR = (uint32)((uint32)0U << 16U) |
(uint32)((uint32)(3U - 1U) << 12U) |
(uint32)((uint32)((5U + 3U) - 1U) << 8U) |
(uint32)((uint32)(3U - 1U) << 6U) |
(uint32)14U; */

// 1Mbps
/* canREG1->BTR = (uint32)((uint32)0U << 16U) |
(uint32)((uint32)(1U - 1U) << 12U) |
(uint32)((uint32)((7U + 1U) - 1U) << 8U) |
(uint32)((uint32)(1U - 1U) << 6U) |
(uint32)8U;*/
canREG1->BTR = (uint32)((uint32)0U << 16U) |
(uint32)((uint32)(1U - 1U) << 12U) |
(uint32)((uint32)((7U + 1U) - 1U) << 8U) |
(uint32)((uint32)(1U - 1U) << 6U) |
(uint32)8U;

These are the old values ..... very very similar but different

/****************************************** PLL1=180MHz ****************************************************/

/*! \brief Definizione costante per impostazione baudrate con PLL1=160MHz e CAN Bit Timing=125K */
#define BRP_180M_125K 25U
#define BRPE_180M_125K 1U
#define PHASE_SEG1_180M_125K 3U
#define PHASE_SEG2_180M_125K 1U
#define SJW_180M_125K 3U

/*! \brief Definizione costante per impostazione baudrate con PLL1=160MHz e CAN Bit Timing=250K */
#define BRP_180M_250K 29U
#define BRPE_180M_250K 0U
#define PHASE_SEG1_180M_250K 4U
#define PHASE_SEG2_180M_250K 4U
#define SJW_180M_250K 4U

/*! \brief Definizione costante per impostazione baudrate con PLL1=160MHz e CAN Bit Timing=500K */
#define BRP_180M_500K 14U
#define BRPE_180M_500K 0U
#define PHASE_SEG1_180M_500K 3U
#define PHASE_SEG2_180M_500K 3U
#define SJW_180M_500K 3U

/*! \brief Definizione costante per impostazione baudrate con PLL1=160MHz e CAN Bit Timing=1M */
#define BRP_180M_1M 8U
#define BRPE_180M_1M 0U
#define PHASE_SEG1_180M_1M 1U
#define PHASE_SEG2_180M_1M 1U
#define SJW_180M_1M 1U

Many many thanks dor your support

Regards

Fabio