Getting started with EMX – updating the bootloader

The first thing that you have to do to get started using EMX from GHIElectronics, www.ghielectronics.com, is to go to http://www.microsoft.com/netmf/default.mspx and download the Micro Framework SDK and install it. Then go over to GHI Electronics, http://www.ghielectronics.com/product/129, and download and install the GHI SDK for NETMF. While you are there be sure to download their free ebook, “Beginners guide to NETMF”. You will of course need Visual Studio. As of this time VS 2008 is supported not VS 2010.

The first thing that you will probably want to do is to update the firmware on the development board. This is accomplished in two steps and involves placing the EMX board into two different operating modes.

Updating the bootloader

Plug the development board into an available USB port on your computer using the supplied USB cable. If the computer asks to install any device drivers, ignore that for now. To access the bootloader update mode, you would hold down the Up, Down and Select buttons on the development board as you power up the board or push the reset button. So patience is called for here. Unless you have teeny tiny fingers, it’s very difficult to hold all three buttons down at the same time. You know you have it when the screen does not display the boot up messages and is washed out with white.

If this is the first time that you have accessed this mode, the Hardware wizard should start up and want to install device drivers.  The drivers you want to install at this time are located at C:\Program Files\GHI Electronics\GHI NETMF v4.0 SDK\USB Drivers\GHI_Bootloader_Interface if you used the default location when you installed the GHI SDK. This driver allows you to connect to the board through the USB port using a terminal program. Once the driver is installed you are ready to go.

You need to use a terminal program to upload the new program to the processor. GHI reccommends Terra Term to use to upload the bootloader, you can download the program from their site. Personally, I have not had any success using Terra Term. I had heard that they have had problems with their 1K XModem protocol and I could never get it to work properly. I have used HyperTerminal that comes with Windows successfully. Start up your terminal program and connect to the EMX board. Hopefully you will be able to figure out which comport you need to use. Use 115200 8-N-1 and no flow control as your parameters.

Once you have connected, use the ‘E’ command to erase the memory. Note that you have to use upper case characters. Then press ‘Y’ to confirm the erase command. Wait until the board memory has been erased. While the erase is going on * characters are printed to the screen. They that stops you are ready to upload the new bootloader.

Press ‘X’ to begin the upload procedure. Again, remember upper case! The terminal program will start printing C characters to the screen indicating that the board is waiting for the upload. If you are using HyperTerminal, click the Transfer menu and Send File. Browse to the bootloader program to upload. In this case you want to go to C:\Program Files\GHI Electronics\GHI NETMF v4.0 SDK\EMX\Firmware\TinyBooter and select the TinyBooter.GHI file. Be sure to select XModem 1K to use for the transfer. The transfer only takes a few seconds. After the transfer is complete, the board will reboot itself in preparation for the next step.