ESP32 Forum

ESP32-S3 max USB_JTAG Speed for Firmware upload

Hello all,

I am using the usb-jtag interface to upload my firmware to the esp32-s3.
Now I wonder if there is a way to increase the upload speed? Is there any hardware related limit?

I am using the VSCode esp-idf extension. In settings.json I can easily change teh baudrate for UART-flashing. But I think there is no option for changing the usb-jtag speed, since this comes from OpenOCD, right? From OpenOCD I get, that the clock speed for usb-jtag upload is 40000 kHz. Is this the upper limit?

Best,
Jonathan

It's mostly limited by the latency of the JTAG commands combined with the speed of the SPI flash. You could try uploading via the serial interface of the USB-serial-JTAG instead, possibly that is faster.