6–2
Chapter 6: JTAG and In-System Programmability in MAX V Devices
IEEE Std. 1149.1 Boundary-Scan Support
Table 6–1. JTAG Instructions for MAX V Devices (Part 2 of 2)
JTAG Instruction
Instruction Code
Description
Selects the IDCODEregister and places it between the TDIand TDO
pins, allowing you to shift the IDCODEregister out of the TDOpin
serially.
IDCODE
00 0000 0110
Places the 1-bit bypass register between the TDIand TDOpins,
which allows the BST data to pass synchronously through target
devices to adjacent devices if the device is operating in normal mode
and tri-stating all the I/O pins.
HIGHZ (1)
CLAMP (1)
00 0000 1011
00 0000 1010
Places the 1-bit bypass register between the TDIand TDOpins,
which allows the BST data to pass synchronously through target
devices to adjacent devices during normal device operation and
holding I/O pins to a state defined by the data in the boundary-scan
register.
Allows you to define the scan chain between the TDIand TDOpins in
the MAX V logic array. Use this instruction for custom logic and
JTAG interfaces.
USER0
USER1
00 0000 1100
00 0000 1110
Allows you to define the scan chain between the TDIand TDOpins in
the MAX V logic array. Use this instruction for custom logic and
JTAG interfaces.
For the instruction codes
of the IEEE 1532
instructions, refer to the IEEE 1532 in-system concurrent (ISC) instructions used if
IEEE 1532
instructions
IEEE 1532 BSDL Files
page of the Altera
website.
programming a MAX V device through the JTAG port.
Note to Table 6–1:
(1) HIGHZ, CLAMP, and EXTESTinstructions do not disable weak pull-up resistors or bus hold features.
w
You must not issue unsupported JTAG instructions to the MAX V device because this
may put the device into an unknown state, requiring a power cycle to recover device
operation.
MAX V Device Handbook
May 2011 Altera Corporation