High speed serial trace protocol for device debug

Abstract

Tracing of test information from a hardware device for debugging is formatted for transmission via a high-speed serial protocol. Data from various components in the hardware device is transmitted to an external test board using high speed serial ports. The number of serial ports needed for data transfer is significantly less than a complimentary parallel port configuration. Additional functional blocks on the chip process the data for high speed serial output. The functional blocks format information into subchannels, arbitrate data, append protocol, perform data integrity checks, and serialize the data. The additional blocks built on the chip to support the serial ports consume less chip space than the space consumed by the number of parallel ports required to provide equivalent data transfer rates. The process operates in near real time and may use time stamping to correlate and reconstruct data from different information sources. An input port receives data from the external test component to modify registers or memory, set break points, modify hardware status, communicate with processors, or modify other operating conditions to debug the hardware device.