How to upload a nxtOSEK program
Intro
For an appli “MyAppli”, nxtOSEK builds 3 different binaries:
- MyAppli_ram.bin, is uploaded in RAM, on bricks without firmware:
- program is lost when the brick is switched off
- useful for quick tests
- on Linux, can be uploaded with fwexec (from libnxt-0.3)
- no tools (simply) available on Windows
- MyAppli_rom.bin, is uploaded in ROM, on bricks running a minimal firmware provided by nxtOSEK: * the minimal firmware can load a single program * on Windows, can be uploaded with appflash.exe, provided by nxtOSEK * no tools for Linux
- MyAppli.rxe, is uploaded in “disk” (actually ROM), on bricks runnig Jon Hansen’s Enhanced Firmware: * same extension as the standard Lego byte-code, but NOT COMPATIBLE * runs on very complete firware, with the same interface as the Lego firmware * uploadable on both Linux and Windows with NexTTool(.exe) * uploadable on Linux with t2n (talk2nxt)
The following table summerizes the results, listing the necessary firware (if any) and the tools available for uploading on Linux and (Cyg)Win:
| Firmware | Linux | (Cyg)Win | |
|---|---|---|---|
| foo_ram.bin | none | fwexec foo_ram.bin | no |
| foo_rom.bin | nxt_bios_rom.rfw | no | appflash.exe |
| foo.rxe | lms_arm_nbcnxc_128.rfw | NeXTTool /COM=usb -download=foo.rxe | NeXTTool /COM=usb -download=foo.rxe |
| or with the script: loadrxe foo.rxe |
Flashing a firmware
Firmware files have the extension “.rfw”, exemples are:
- nxt_bios_rom.rfw, from the nxtOSEK distrib (nxtOSEK/ecrobot/bios/)
- lms_arm_nbcnxc_128.rfw, from Jon Hansen’s NeXTTool
- or the standard Lego firmware
If any firmware is installed, the brick must be reset first:
- press the reset button for 4 seconds (tiny button on the hole under the USB socket)
- press the orange button, the brick will be in uplod mode (blank screen, emiting a tic-tic sound)
Linux
On Linux, only root can access the brick USB port, thus you have to “sudo” the commands. On recent Debian/Ubuntu distributions using udev, you can bypath this problem by copying the ad-hoc rule file 70-lego.rules in /etc/udev/rules.d/. You can use the fwflash command from libnxt-0.3:
fwflash file.rfw
or the Linux port of the NexTTool program:
NeXTTool /COM=usb -firmware=file.rfw
Windows
Use NexTTool command line in a windows or cygwin terminal:
NeXTTool.exe /COM=usb -firmware=file.rfw
You can also use the Lego Mindstorm graphical interface, if installed (menu Tools/Upgrade Firmware).