# US 10,481,990 B2 · Apparatuses and methods for a multiple master capable debug interface > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,481,990 B2 - Document ID: US10481990B2 - Status: Granted - Kind: B2 - Application number: 15/474,799 - Filed: 2017-03-30 - Published: 2017-12-14 - Granted: 2019-11-19 - Earliest claimed: 2016-06-13 - Assignees: Intel Corporation - Applicants: Intel Corporation - Inventors: Patrik Eder; Rolf H. Kuehnis; Enrico D. Carrieri - Web page: https://patentgrep.com/patent/US10481990B2 ## CPC - G06F 11/25: Testing of logic operation, e.g. by logic analysers - G06F 11/267: Reconfiguring circuits for testing, e.g. LSSD, partitioning - G01R 31/31705: {Debugging aspects, e.g. using test circuits for debugging, using dedicated debugging test circuits (generation of test sequences therefor G01R31/31835, using scan test therefor G01R31/318544)} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract Methods and apparatuses relating to a multiple master capable debug interface are described. In one embodiment, an apparatus includes a device circuit, a debug and test access port to debug and test the device circuit, and a switching circuit to switch a debug and test mastership between the debug and test access port and a data access port to the device circuit that is not dedicated to debug and test. ## Claims ### Claim 1 An apparatus comprising: a device circuit; a debug and test access port to debug and test the device circuit; and a switching circuit to switch a debug and test mastership between the debug and test access port and a data access port to the device circuit that is not dedicated to debug and test. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the switching circuit is to provide the debug and test mastership to a first requestor of the debug and test access port and the data access port. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the switching circuit is to provide the debug and test mastership to one of the debug and test access port and the data access port and only transfer the debug and test mastership when granted by the switching circuit in response to a request for the debug and test mastership. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the debug and test mastership is acknowledged according to a Joint Test Action Group (JTAG) standard. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the debug and test access port is a physical connector to the device circuit and the data access port is a wireless connector to the device circuit. ### Claim 6 (depends on 5) The apparatus of claim 5, further comprising a debug and test tool to wirelessly connect to the wireless connector. ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the debug and test tool wirelessly connects through the wireless connector to a multiple pin Joint Test Action Group (JTAG) interface. ### Claim 8 (depends on 6) The apparatus of claim 6, wherein the device circuit further comprises an internal debug and test tool. ### Claim 9 A method comprising: providing a device circuit and a debug and test access port to debug and test the device circuit; switching a debug and test mastership with a switching circuit between the debug and test access port and a data access port to the device circuit that is not dedicated to debug and test; and performing a debug and test operation on the device circuit. ### Claim 10 (depends on 9) The method of claim 9, further comprising providing the debug and test mastership to a first requestor of the debug and test access port and the data access port. ### Claim 11 (depends on 9) The method of claim 9, further comprising: providing the debug and test mastership to one of the debug and test access port and the data access port, and only transferring the debug and test mastership when granted by the switching circuit in response to a request for the debug and test mastership. ### Claim 12 (depends on 9) The method of claim 9, further comprising acknowledging the debug and test mastership according to a Joint Test Action Group (JTAG) standard. ### Claim 13 (depends on 9) The method of claim 9, further comprising providing the debug and test access port as a physical connector to the device circuit and the data access port as a wireless connector to the device circuit. ### Claim 14 (depends on 13) The method of claim 13, further comprising wirelessly connecting a debug and test tool to the wireless connector. ### Claim 15 (depends on 14) The method of claim 14, wherein the wirelessly connecting comprises wirelessly connecting the debug and test tool through the wireless connector to a multiple pin Joint Test Action Group (JTAG) interface. ### Claim 16 (depends on 14) The method of claim 14, wherein the providing further comprises providing the device circuit having an internal debug and test tool. ### Claim 17 A computing system comprising: a plurality of devices; a debug network coupled between the plurality of devices and dedicated to debug and test, wherein each of the plurality of devices comprises an internal test and debug tool, and a debug and test access port coupled to the debug network; and a switching circuit to switch a debug and test mastership between: an internal test and debug tool of a first device of the plurality of devices and couple the internal test and debug tool of the first device to all other devices of the plurality of devices through the debug and test access port of the first device, and an internal test and debug tool of a second device of the plurality of devices and couple the internal test and debug tool of the second device to all other devices of the plurality of devices through the debug and test access port of the second device. ### Claim 18 (depends on 17) The computing system of claim 17, wherein the plurality of devices comprises at least three devices, and the switching circuit is to further switch the debug and test mastership between an internal test and debug tool of a third device of the plurality of devices and couple the internal test and debug tool of the third device to all other devices of the plurality of devices through the debug and test access port of the third device. ### Claim 19 (depends on 17) The computing system of claim 17, wherein when the switching circuit switches the debug and test mastership to an internal test and debug tool of a device of the plurality of devices, the switching circuit is to disconnect an internal test and debug tool of each of the other devices from the debug network. ### Claim 20 (depends on 17) The computing system of claim 17, wherein the switching circuit is to provide the debug and test mastership to a first requesting device of the plurality of devices. ### Claim 21 (depends on 17) The computing system of claim 17, wherein the switching circuit is to provide the debug and test mastership to one of the plurality of devices and only transfer the debug and test mastership when granted by the switching circuit in response to a request for the debug and test mastership. ### Claim 22 (depends on 17) The computing system of claim 17, wherein the debug and test mastership is acknowledged according to a Joint Test Action Group (JTAG) standard. ### Claim 23 (depends on 17) The computing system of claim 17, wherein the debug network is a multiple pin Joint Test Action Group (JTAG) interface. ### Claim 24 (depends on 17) The computing system of claim 17, wherein the switching circuit is to further switch each device of the plurality of devices between a first mode where an internal debug and test tool of a device is connected to all other devices of the plurality of devices through a debug and test access port of the device, and a second mode where the internal debug and test tool of the device is not connected to any other device of the plurality of devices through the debug and test access port of the device.