In a typical development environment, the LM3S8962-EVAL board boots from internal flash into the GDB Stubrom. eCos applications are configured for RAM startup and then downloaded and run on the board via the debugger arm-eabi-gdb.
For serial communications, the Stubrom runs with 8 bits, no parity, and 1 stop bit at 38400 baud. This rate can be changed in the platform HAL configuration. Under normal circumstances, the Stubrom runs in-place from the internal Flash.
Programming The Stubrom
To program the Stubrom into the internal flash either a JTAG debugger that understands the LM3S flash may be used, such as a Ronetix PEEDI or an Abatron BDI3000, or the TI LM Flash Programmer may be used. Configuration files for the PEEDI and BDI3000 are supplied in the LM3S8962-EVAL HAL package, and brief instructions for downloading the Stubrom are given in there. If no JTAG debugger is available, then the Stubrom must be downloading using the LM Flash Programmer. The following are brief instructions for doing this. The reader is referred to the documentation that comes with the loader for full details.
Download the LM Flash Programmer and Stellaris FTDI Windows driver either from TI or Luminary Micro websites, or from the CD supplied with the board and install it on a PC running Windows that has an available USB port.
Copy the file stubrom.bin to a suitable location on the Windows PC.
Connect the USB cable supplied with the board between the board and the PC. Follow any instructions to install the driver.
Start the LM Flash Programmer and in the Configuration tab select the LM3S8962 Ethernet an CAN evaluation board.
In the Program tab either type in or browse to the stubrom.bin file. Select "Erase Entire Flash" and "Verify After Program". Ensure that the "Program Address Offset" is zero.
Press "Program" button and the loader should download and verify the binary file. The programming is now complete and the LM Flash Programmer can now be exited.
Whatever mechanism is used to program the Stubrom, something similar to the following output should be seen on the Windows USB virtual COM port when the reset button is pressed:
Rebuilding The Stubrom
Should it prove necessary to rebuild the Stubrom binary, this is done most conveniently at the command line. The steps needed to rebuild the the ROM version of the Stubrom are:
$ mkdir stubs_lm3s8962_rom $ cd stubs_lm3s8962_rom $ ecosconfig new lm3s8962 stubs $ ecosconfig resolve $ ecosconfig tree $ make
At the end of the build the install/bin subdirectory should contain the file stubrom.bin.