JTAG TAP Block Diagram
Boundary Scan Register
ID Code Register
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Test Access Port (TAP) Controller
Identification (ID) Register
The ID Register is a 32-bit register that is loaded with a device and vendor specific 32-bit code when the controller is put in
Capture-DR state with the IDCODE command loaded in the Instruction Register. The code is loaded from a 32-bit on-chip ROM.
It describes various attributes of the RAM as indicated below. The register is then placed between the TDI and TDO pins when the
controller is moved into Shift-DR state. Bit 0 in the register is the LSB and the first to reach TDO when shifting begins.
Rev: 1.04 10/2004
Specifications cited are subject to change without notice. For latest documentation see http://www.gsitechnology.com.
© 2002, GSI Technology