## Carbide On-device Debug Agent

The Carbide On-device Debug Agent (CODA) is a program that enables on-device debugging of phone prototypes, reference boards, and retail phones. An on-device debug agent is a program that is installed on a phone or reference board. It communicates with the debugger using a serial-over-Bluetooth or serial-over-USB connection. Through this serial communication, the on-device debug agent acts as the interface between the Carbide.c++ debugger and the target device. The CODA provides:

- Debug agent running on Symbian OS
- Provides a stable & integrated interface to Symbian OS
- Used to debug applications on actual devices
- Can be built-in to the OS image or installed as a .sis file

Using the on-device remote agent, one can use the Carbide.c++ IDE to debug programs running on phone hardware, making the debugging process much easier. The on-device debug agent works on all Nokia Qt SDK, Symbian^3, and Symbian TechView devkits.

The Application CODA is stored online and available for download and installation using the On-Device Connections > New Connection Wizard > Install remote agents pane.

Some of the key benefits to using an on-device debug agent include:

- Easy debugging via serial interface (Bluetooth, USB, IrDA, etc)
- More accurate than emulator debugging
- Can often avoid using expensive hardware debuggers

There are two variations of the on-device debug agent, they are:

- Application CODA—supports application debugging only and available to developers creating applications for devices. Developers do not have access to system level routines, system ROM, other user application code, cannot modify the LR and SR registers, and must use a SIS file to debug an application.
- System CODA— supports both application and limited ROM debugging (includes application executables and limited ROM based components (i.e. no device drivers) and available to original equipment manufacturers (OEM) for device creation and customization

##### Related tasks

- On-device Debugging Overview