TCAN1145-Q1: Interface forum

WeiJie Lin

Part Number: TCAN1145-Q1

Tool/software:

Hello TI Team,

I'm working on developing the PN wake-up feature for the TCAN1145, but I can't get it to wake up from sleep mode. Can you help me figure out what's going wrong?

My test flow:

(1) When the MCU powers up, it initializes the TCAN1145 and sets it to Normal mode.

(2) The MCU starts sending CAN packets. After sending 500 packets, the TCAN1145 is set to Sleep mode.

(3) When a specific packet is received, the MCU can detect the wake-up signal by checking the TCAN1145's INH pin.

For the initialization of the TCAN1145, I followed TI's official documentation: "How Selective Wake Enables Partial Networking."

I referred to Table 5-4 (Valid Data Programming) and according to the test instructions, when the TCAN1145 receives 0x01 0x80, the TCAN1145's INH pin should go from low to high. However, I'm not seeing this happen.

Here is my initialization process:

(1) Reg=0x17, Data=0x02 //TCAN1145 software reset

(2) Reg=0x47, Data=0x00

(3) Reg=0x30, Data=0x00

(4) Reg=0x31, Data=0x00

(5) Reg=0x32, Data=0x04

(6) Reg=0x33, Data=0x8C

(7) Reg=0x34, Data=0x00

(8) Reg=0x35, Data=0x00

(9) Reg=0x36, Data=0x00

(10) Reg=0x37, Data=0x00

(11) Reg=0x38, Data=0x25

(12) Reg=0x39, Data=0x01

(13) Reg=0x40, Data=0x80 //I suspect there's a typo in the official documentation. I changed the address to 0x3A (the document states 0x40).

(14) Reg=0x44, Data=0xD0

(15) Reg=0x46, Data=0xFE

(16) Reg=0x47, Data=0x80

(17) Reg=0x10, Data=0x87 //TCAN1145 entry NormalMode

(18) MCU sending 500 CAN packets

(19) Reg=0x10, Data=0x81 //TCAN1145 entry SleepMode

(20) I used another CAN transceiver to send 0x01 0x80 on the bus, but the TCAN1145's INH pin didn't react at all.

Is there anything wrong with my software settings? Or do I need to confirm something on the hardware?

Hope to get your support as soon as possible, thank you!!

over 1 year ago

0 Eric Schott1 over 1 year ago

TI__Guru 53555 points

Hi WeiJie,

Your configuration method here looks correct. All of the appropriate registers have been configured, the SW_CFG bit has been set, and the device has been put into sleep mode with SW_EN set. If all the configured values match the WUF on the bus including the ID, DLC, and data, then this should wake the device from sleep mode and the INH signal will drive high.

Have you been able to confirm that SPI communication is working well between the transceiver and your MCU? A good way to check this is to write to and read from the scratchpad register 0Fh. This will ensure that the system is able to read and write correctly between the two devices.

Are you sure that the MCU is formatting the register address correctly? The first 7 bits of the transaction should be the address field and the last bit is the read/write bit. This means that the actual byte value of a write to the mode control register (address = 10h) would be 0x21

Are you sure that the ID of the wake up frame matches what is configured for the transceiver? Have you been able to test the device will the data mask enabled to see if wake via the CAN ID alone is working properly?
Please ensure that the wake up frame is being transmitted as a classic CAN frame (FD bit and BRS disabled) so that bit rate is constant throughout the frame. Note that partial networking does not support CAN FD frames.
If communication continues for while, do you observe the TCAN1145 wake up eventually due to a frame_overflow? This could indicate that the transceiver in unable to decode CAN communication possibly due to a misconfigured data rate or noise in the system.

Let me know if any of these tips help resolve this issue and if I can be of any more help. If none of these reveal the problem, I will probably ask you to share wakeforms of the CAN bus during the wake up frame to confirm that the message is being properly received by the transceiver.

Regards,
Eric Schott

0 WeiJie Lin over 1 year ago in reply to Eric Schott1

Prodigy 10 points

Hi Eric,

Thank you for your prompt response.

(1) I've confirmed that the SPI communication is working correctly. I wrote 0x50 to register 0x0F and read it back, confirming that the value is also 0x50.

(2) I'm currently testing if I can wake up the system using a CAN ID. I can successfully wake it up with just the CAN ID, but not with the CAN ID and DATA combination. For example, my wake-up settings are ID=0x123 and DATA=0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08. However, when I send ID=0x123 and DATA=0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF, 0xAA, 0xBB on the CAN bus, it still wakes up the system.

Here is my initialization process. I'm not sure where I might have gone wrong.

Step	Description	Register	Register(Hex)	Data(Hex)	MCU Send	TCAN1145 Rsp
0	TCAN11145 software reset	DEVICE_RST	19	02	33 02	E0 00
Delay 5ms
1	Clear all INT	INT_1	51	FF FF FF	A3 FF FF FF	E0 00 00 00
2	Clear all INT	INT_CANBUS	54	FF	A9 FF	00 00
3	Disable selective wake	SW_CONFIG_4	47	00	8F 00	00 00
4	Write desired WUF ID (0x123)	SW_ID1	30	00	61 00	00 00
5	Write desired WUF ID (0x123)	SW_ID2	31	00	63 00	00 00
6	Write desired WUF ID (0x123)	SW_ID3	32	04	65 04	00 00
7	Write desired WUF ID (0x123)	SW_ID4	33	8C	67 8C	00 00
8	Write ID mask to (0) SW_ID_MASK1	SW_ID_MASK1	34	00	69 00	00 00
9	Write ID mask to (0) SW_ID_MASK2	SW_ID_MASK2	35	00	6B 00	00 00
10	Write ID mask to (0) SW_ID_MASK3	SW_ID_MASK3	36	00	6D 00	00 00
11	Write ID mask to (0) SW_ID_MASK4	SW_ID_MASK4	37	00	6F 00	00 00
12	Read ID mask to (0) SW_ID_MASK4	SW_ID_MASK4	37	00	6E 00	00 00
13	Write ID mask (0×001), DLC (8), and DATA_MASK_EN (1)	SW_ID_MASK_DLC	38	31	71 31	00 00
14	Set Data[0]=0x01	Data1	39	01	73 01	00 00
15	Set Data[1]=0x02	Data2	3A	02	75 02	00 00
16	Set Data[2]=0x03	Data3	3B	03	77 03	00 00
17	Set Data[3]=0x04	Data4	3C	04	79 04	00 00
18	Set Data[4]=0x05	Data5	3D	05	7B 05	00 00
19	Set Data[5]=0x06	Data6	3E	06	7D 06	00 00
20	Set Data[6]=0x07	Data7	3F	07	7F 07	00 00
21	Set Data[7]=0x08	Data8	40	08	81 08	00 00
22	Configure arbitration speed, FD:CAN ratio, and SW_FD_PASSIVE (1)	SW_CONFIG_1	44	D0	89 D0	00 00
23	Set frame overflow to 255 (maximum number of errors before wake up)	SW_CONFIG_3	46	FE	8D FE	00 00
24	Set SWCFG bit (configuration is complete)	SW_CONFIG_4	47	80	8F 80	00 00
25		MODE_CNTRL	10	00	20 00	00 04
26	TCAN1145 entry normal mode	MODE_CNTRL	10	07	21 07	00 00
27	TCAN1145 start working	MODE_CNTRL	10	87	21 87	00 00
MCU Tx CAN packet
29		MODE_CNTRL	10	00	20 00	00 87
30	TCAN1145 entry sleep mode	MODE_CNTRL	10	81	21 81	00 00

I hope you can assist me. Thank you

0 Eric Hackett over 1 year ago in reply to WeiJie Lin

TI__Guru 74282 points

WeiJie,

US holiday starts tomorrow, with many people taking off today and Friday. Please expect a delay in responses until Monday (07/08/2024) next week. Thank you for your patience.

Regards,

Eric Hackett