gnwmanager/tutorials/flash.md

Flashing Firmware

GnWManager can efficiently flash compiled binaries to the following locations:

1. Internal Flash Bank 1 (bank1)
2. Internal Flash Bank 2 (bank2)
3. External SPI Flash (ext)
4. An exact virtual memory address (e.g. 0x08000000 for bank 1)

When flashing data, GnWManager will only flash chunks of data that have changed, speeding up the process and reducing flash wear.

Flash Example

The following command will flash a hypothetical binary located at build/gw_retro_go_intflash.bin to the first internal bank.

gnwmanager flash bank1 build/gw_retro_go_intflash.bin

Commonly external binary payloads may be flashed at an offset (for example, if dual booting with patched firmware).

gnwmanager flash ext build/gw_retro_go_extflash.bin --offset=1MB

Offsets in gnwmanager can be specified as plain integer bytes (1048576), as plain hex (0x100000), or as a decimal with units (1MB).

The following commands are all equivalent:

gnwmanager flash ext build/gw_retro_go_extflash.bin --offset=1048576
gnwmanager flash ext build/gw_retro_go_extflash.bin --offset=0x100000
gnwmanager flash ext build/gw_retro_go_extflash.bin --offset=1MB
gnwmanager flash 0x90000000 build/gw_retro_go_extflash.bin --offset=1MB
gnwmanager flash 0x90100000 build/gw_retro_go_extflash.bin

Command Chaining

Frequently, we will want to flash multiple binary payloads to different sections. Commands can be chained in a single GnWManager session, delimited by --. Each command is interpreted independently.

The following command is also separated on multiple lines for readability.

gnwmanager \
    flash bank1 build/gw_retro_go_intflash.bin \
    -- flash ext build/gw_retro_go_extflash.bin \
    -- start bank1