The eCos Developer’s Kit package comes with a ROM
which provides GDB support for the Hitachi EDK7708 board (a big-endian
and a little-endian version). Images of these ROMs are also provided
at loaders/sh-edk7708/gdbload.bin and
loaders/sh-edk7708le/gdbload.bin under
the root of your eCos installation.
The ROM is installed to socket U6 on the board. When using
the big-endian ROM, jumper 9 must be set to 2-3. When using the
little-endian ROM, jumper 9 must be set to 1-2. Attention should
be paid to the correct orientation of the ROM during installation.
Only replace the board"s existing ROM using a proper PLCC extraction
tool, as the socket would otherwise risk being damaged.
If you are going to program a new ROM or FLASH using the binary
image, you may have to experiment to get the right byte-order in
the device. Depending on the programming software you use, it might
be necessary to enable byte-swapping. If the GDB stub ROM/FLASH
you program does not work, try reversing the byte-order.
The GDB stub in the EPROM allows communication with GDB using
the serial port at connector J1. The communication parameters are
fixed at 38400 baud, 8 data bits, no parity bit and 1 stop bit (8-N-1).
No flow control is employed. Connection to the host computer should
be made using the dedicated serial cable included in the EDK package.
These two binary preparation steps are not strictly necessary
as the eCos distribution ships with pre-compiled binaries in the
directory loaders/sh-edk7708 and loaders/sh-edk7708le
relative to the installation root.