JTAG support — Usage

Use of JTAG for debugging

JTAG can be used to single-step and debug loaded applications, including RedBoot. Only ROM configuration applications should be debugged using JTAG, RAM applications assume the presence of RedBoot.

Ronetix PEEDI notes

On the Ronetix PEEDI, the peedi.sd_l137.cfg file should be used to setup and configure the hardware to an appropriate state to load programs. This includes setting up the PLLs and SDRAM controller.

The peedi.sd_l137.cfg file also contains an option to define whether hardware or software breakpoints are used by default, using the CORE0_BREAKMODE directive in the [PLATFORM_ARM] section. Edit this file if you wish to use hardware break points, and remember to restart the PEEDI to make the changes take effect.

On the PEEDI, debugging can be performed either via the telnet interface or using arm-eabi-gdb and the GDB interface. In the case of the latter, arm-eabi-gdb needs to connect to TCP port 9000 on the PEEDI's IP address. For example:

(gdb) target remote 111.222.333.444:9000

The target will always run the primary and secondary bootloaders because the ARM is not powered up until the secondary bootloader has activated the ARM and put the DSP to sleep. The PEEDI will then run the initialization section of the peedi.sd_l137.cfg file, and halt the target. This behaviour is repeated whenever the board is powercycled. If the PEEDI is given a 'go' command then the board will continue booting as normal.

Consult the PEEDI documentation for information on other features.

Running ROM applications

Applications configured for ROM startup can be run directly under JTAG. Once loaded and running via JTAG, HAL diagnostic output will appear by default on the serial debug port.