topic LPCXpresso55S36 I3C SDK examples not working (possible SDA risetime issue) in LPC Microcontrollers

LPCXpresso55S36 I3C SDK examples not working (possible SDA risetime issue)

amonreal — Fri, 21 Apr 2023 00:05:44 GMT

Hi,

I am working on an LPCXpresso 55S36 and using SDKs "lpcxpresso55s36_i3c_polling_b2b_transfer_master" and "lpcxpresso55s36_i3c_master_read_sensor_icm42688p" and I haven't been able to make either of them work properly.
It seems like the SCL line (J9 pin 20) is working properly but I see a really long rise time on the SDA line (J9 pin 18). I have attached an oscilloscope capture for both SDKs

Could I have a setup issue, my board be damaged, or have you seen this type of issue before? Does the SDA line require a pullup? Thanks

Best,
Antonio

Re: LPCXpresso55S36 I3C SDK examples not working (possible SDA risetime issue)

Alice_Yang — Fri, 21 Apr 2023 07:12:15 GMT

Hello @amonreal

Please refer to readme.txt to configure your board:

Alice

Re: LPCXpresso55S36 I3C SDK examples not working (possible SDA risetime issue)

amonreal — Fri, 21 Apr 2023 20:54:39 GMT

Hi @Alice_Yang

Thanks for your reply. I did do all those steps when I got these captures as you can see from the third picture attached on my original post. Do you have any more pointers?

Re: LPCXpresso55S36 I3C SDK examples not working (possible SDA risetime issue)

Alice_Yang — Sun, 23 Apr 2023 02:17:27 GMT

Hello @amonreal

If run the demo "lpcxpresso55s36_i3c_polling_b2b_transfer_master", need connect with another board as slave. About the demo "lpcxpresso55s36_i3c_master_read_sensor_icm42688p", I tested it before, it can well, no issue, recommend you check carefully again refer to readme.txt.

Alice