Patent ID: 6996747
Filing Date: 2006-02-07
Classification: G01R,G06F

Abstract:
1. A data processing device formed on a substrate of semiconductor material comprising: A. program counter means for controlling program instruction addresses in the data processing device; B. program counter stack means connected to the program counter means for holding the contents of the program counter; C. program counter trace stack means connected to the program counter for holding program instruction addresses from the program counter means; and D. serial scan path means, including an access port, a scan data input lead connected to the access port, a scan data output lead, serial scan registers connected between the scan data input and output leads and coupled to the access port, a scan clock input lead connected to the access port, and a scan mode select input lead connected to the access port, the serial scan registers being selectively connected to the program counter trace stack means, the serial scan path means for transmitting to external the data processing device, on the scan data output lead, program instruction addresses from the program counter trace stack means.