But then what? He needed a JTAG programmer to work with the chip. Like any good autodidact he choose to make his own rather than buying one. He absorbed the JTAG specification and coded a bit ...

Test Data Register (TDR): The access network consists of Test Data Register (TDR), which is similar to, but not the same as those found in JTAG Boundary Scan Standard. TDR has data input ports, si, to ...

JTAG by itself for both control and data transfer JTAG (mainly for control and lower speed and bandwidth operations) plus AUX interfaces (mainly for higher bandwidth data transfer) AUX ports by ...