The descriptions are followed by descriptions of each target, providing specific details of how to set up the target (if hardware) and the necessary communication information (such as baud rate for hardware targets, or special connection options for simulator targets).
Most targets will have eCos GDB stubs or CygMon installed. These normally wait for GDB to connect at 38400 baud, using 8 data bit, no parity bit and 1 stop-bit (no hardware flow control). Check the section for your target to ensure it uses this speed. If not, adjust the following instructions accordingly.
The following instructions depend on you to select the appropriate serial port on the host - the serial port which connects to the target's (primary) serial port. On Linux this could be /dev/ttyS0, while the same port on Windows would be named COM1, or
/dev/ttya on Solaris. Substitute the proper serial port name in the below.
Some targets allow GDB to connect via Ethernet - if so, it will be mentioned in the section describing the target. Substitute the target's assigned IP address or hostname for <hostname> in the following. The <port> is the TCP port which the eCos GDB stub or CygWin is listening on. It is also listed in the section describing the target.
GDB connects to all simulator targets using the same basic command, although each simulator may require additional options. These are listed in the section describing the target, and should be used when connecting.
Synthetic targets are special in that the built tests and applications actually run as native applications on the host. This means that there is no target to connect to - the test or application can be run directly from the GDB console using:
or from Insight by pressing the Run icon. There is therefore no need to connect to the target or download the application, so you should ignore GDB "target" and "load" commands in any instructions found in other places in the documentation.
The eCos Developer's Kit package comes with an EPROM which provides GDB support for the NEC VRC4373 evaluation board. An image of this EPROM is also provided at loaders/vr4300-vrc4373/gdbload.bin under the root of your eCos installation.
The EPROM is installed to socket U12 on the board. Attention should be paid to the correct orientation of the EPROM during installation. Only replace the board's existing ROM using a proper PLCC extraction tool, as the socket would otherwise risk getting damaged.
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 a straight-through serial cable.
For the synthetic target, eCos relies on features not available in native compilers earlier than gcc-2.95.1. It also requires version 2.9.5 or later of the GNU linker. If you have gcc-2.95.1 or later and ld version 2.9.5 or later, then you do not need to build new tools. eCos does not support earlier versions. You can check the compiler version using gcc -v or egcs -v , and the linker version using ld -v .
If you have native tools that are sufficiently recent for use with eCos, you should be aware that by default eCos assumes that the tools i686-pc-linux-gnu-gcc, i686-pc-linux-gnu-ar, i686-pc-linux-gnu-ld, and i686-pc-linux-gnu-objcopy are on your system and are the correct versions for use with eCos. But instead, you can tell eCos to use your native tools by editting the configuration value "Global command prefix" (CYGBLD_GLOBAL_COMMAND_PREFIX) in your eCos configuration. If left empty (i.e. set to the empty string) eCos will use your native tools when building.