Configuration & Testing
Table 3–1. Cyclone II JTAG Instructions (Part 2 of 2)
JTAG Instruction
Instruction Code
Description
Allows configuration of I/O standards through the JTAG chain for
JTAG testing. Can be executed before, after, or during
configuration. Stops configuration if executed during configuration.
Once issued, the CONFIG_IOinstruction holds nSTATUSlow to
reset the configuration device. nSTATUSis held low until the
device is reconfigured.
CONFIG_IO
00 0000 1101
SignalTap II
instructions
Monitors internal device operation with the SignalTap II embedded
logic analyzer.
Note to Table 3–1:
(1) Bus hold and weak pull-up resistor features override the high-impedance state of HIGHZ, CLAMP, and EXTEST.
The Quartus II software has an Auto Usercode feature where you can
choose to use the checksum value of a programming file as the JTAG user
code. If selected, the checksum is automatically loaded to the USERCODE
register. In the Settings dialog box in the Assignments menu, click Device
& Pin Options, then General, and then turn on the Auto Usercode
option.
Altera Corporation
February 2007
3–3
Cyclone II Device Handbook, Volume 1