Support no-flash design and boot from USB

(KL720 only)

KL720 can be designed to boot up as a USB-DFU device.

When KL720 is in USB-DFU mode, we can use Minion ( SDK/firmware/utils/minion/ ) to download firmware to KL720 internal ram space via USB port, therefore KL720 can boot from USB directly without external flash.

1. Minion

Hardware:

Set bootstrap to manual boot 3. USB or boot from USB directly

Driver installation:

Minion uses libusb for usb access, so on Windows you have to register the device with the WinUSB driver, for more details please refer to Kneron Doc -> Kneron PLUS-c -> Introduction -> Install Dependency -> section 2.1.3 .

Examples:

Please refer to kneron_plus usb_dfu_scan_download() and _load_firmware_to_720() for more details.

Reference : Kneron Doc -> Kneron PLUS-C -> introduction -> run_examples_enterprise -> 7. Load Firmware through Usb for No-Flash Device

2. Firmware build with no-flash design

Project.h:

In board setting section, please set FLASH_TYPE definition as FLASH_TYPE_NULL.

#define FLASH_TYPE                              FLASH_TYPE_NULL

Remove flash related drivers:

Please be noted that all the flash read/write functions are not allowed to be used in no-flash design.