External debug card sharing a communication bus

Abstract

A debug card suitable for use with a data processing system is disclosed. The card includes a microcontroller, a storage device connected to the microcontroller; and, connected to the microcontroller, means for tapping into a communication bus of the data processing system where the bus communicates information between a processor of the data processing system and a display panel. The microcontroller is configured to record the information received by the display panel from the processor in the storage device when the debug card is connected to the communication bus. In one embodiment, the communication bus and the microcontroller are I2C compliant. In this embodiment, the debug card may have its own I2C address thereby enabling the debug card to communicate with the processor. The debug card may further include a serial port connected to the microcontroller. The serial port enables downloading the information stored in the storage device to an external computer. In addition, a user of the external computer may send commands to the data processing system through the serial port to customize the debug session. The debug card may further include a non-volatile storage device containing software enabling the microcontroller to communicate information to the processor. The means for tapping into the communication bus may include a tee connector having a debug port and a communication bus port. In this embodiment, a communication bus ribbon cable is connected to the communication bus port and a debug cable is connected to the debug port. At least a portion of the signals of the communication bus are routed to the debug card via the tee connector and the debug cable. The debug card may include a battery connected to the storage device and suitable for retaining the information in the storage device when external power to the debug card is disconnected.

Dependencies are inferred from the claim text.