Using USB via ISP for flashing (MCXA175VLH)

[KKU]

Dear all,

We have migrated an existing design from an LPC1315 to the new MCXA175VLH. We generally use USB in ISP mode to upload the software. This works without any problems with the LPC1315 (and countless other processors). With the MCXA175VLH, however, no message appears after connecting to the PC. The ISP pin P0.6 is set to low, and the RESET pin is also being handled correctly. The two lines, DP+ and DM-, are each connected to the PC via a 33-ohm resistor.

The processor itself is working properly—access via SWDIO works flawlessly—so the debugger works as well.

Any ideas?

[luis_maravilla]

Hello

According to  UG10365: MCX A175 Hardware Design Guide Chapter 6.3 ISP Programming and Table 13; The MCX A17 only support Universal Asynchronous Receiver/Transmitter (UART) as Serial Peripheral Interface (SPI) interface. Inter-Integrated Circuit (I2C), SPI, and Universal Serial Bus (USB) ISP interfaces are not supported.

The USB connection won't be read in this context, so please add the UART ISP connection instead.

If you are designing a MCXA175 custom board, please refer to this Hardware design guide for more recommendations and instructions

Best Regards, Luis