Unable to find destination disk (Autodetect Error)
Please select it in platformio.ini using the upload_port keyword (Redirecting...) or copy the firmware (.pio/build/LPC1769/firmware.bin) manually to the appropriate disk
Configuring upload protocol…
AVAILABLE: blackmagic, cmsis-dap, jlink, mbed
CURRENT: upload_protocol = mbed
Looking for upload disk…
Error: Please specify upload_port for environment or use global --upload-port option.
For some development platforms it can be a USB flash drive (i.e. /media//)
*** [upload] Explicit exit, status 1
============================================================= [FAILED] Took 13.32 seconds =============================================================
Environment Status Duration
LPC1769 FAILED 00:00:13.320======================================================== 1 failed, 0 succeeded in 00:00:13.320 ========================================================
After the compilation is successful, a firmware.bin file will be generated in the .pioenvs\LPC1768 directory. We will copy this file to the TF card of the motherboard, and then reset the motherboard, so that the firmware is burned into the motherboard.
So since your board doesn’t have any SWD / JTAG debugger probe on board per it’s schematics, the only sensible “upload” method is mbed, which looks for the first available USB diskdrive and copies the firmware.bin there. It’s not a direct upload in your case.
The available upload methods for the LPC1769 (and 8) haven’t changed since the creation of the file in 2018. I can’t see how a direct upload would be possible to the board since it’s not exposing a USB drive for uploading (like the STM32 nucleo boards do through their STLink) and it doesn’t have an on-board debug probe. So the best PlatformIO can do is copy the firmware.bin file to an external drive or the SD if it detects one (your error message indicates none was connected), but one still has to put the SD card in the printer afterwards.
As I said, yes, PlatformIO can “upload” to an SD card. That means copying the file onto it. Not direct uploading to the microcontroller. That’s exactly what’s happnening in the video. It says “Use manually specified D:” and with the standard upload_protocol = mbed it uploads there. The difference to your setup is that somewhere upload_port = D:\ was specified in the LPC1769 environment of the platformio.ini to force “uploading” there.
Do you have an SD card inserted in your computer? What drive letter does it have?