Chapter 9: Configuration, Design Security, and Remote System Upgrades in the Cyclone III Device Family
9–63
Configuration Features
■
To allow the controllers to properly recognize a successful JTAG programming
that results in the device reaching user mode
The ACTIVE_DISENGAGEinstruction is required before JTAG programming regardless
of the current state of the Cyclone III device family if the MSEL pins are set to an
active configuration scheme (AS or AP). If the ACTIVE_DISENGAGEinstruction is issued
during a passive configuration scheme (PS or FPP), it has no effect on the Cyclone III
device family. Similarly, the CONFIG_IOinstruction is issued after an
ACTIVE_DISENGAGEinstruction, but is no longer required to properly halt
configuration. Table 9–20 lists the required, recommended, and optional instructions
for each configuration mode. The ordering of the required instructions is a hard
requirement and must be met to ensure functionality.
(1)
Table 9–20. JTAG Programming Instruction Flows
Configuration Scheme and Current State of the Cyclone III Device
Prior to User Mode
(Interrupting
User Mode
Power Up
JTAG Instruction
Configuration)
AP
AP
AP
PS
FPP
AS
PS FPP AS
PS FPP AS
(2)
(2)
(2)
FACTORY
NA
O
NA
O
NA
R
NA NA NA NA NA
R
O
R
O
R
R
NA
R
ACTIVE_DISENGAGE
CONFIG_IO
R
O
O
R
O
O
O
R
O
O
O
R
O
O
O
R
R
O
O
R
Rc
O
Rc
O
O
NA NA NA NA
Other JTAG instructions
JTAG_PROGRAM
O
O
R
O
R
O
R
O
R
R
R
R
CHECK_STATUS
Rc
R
Rc
R
Rc
R
Rc Rc Rc Rc Rc Rc
Rc
R
Rc Rc
JTAG_STARTUP
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
JTAG TAP Reset/ other instruction
Notes to Table 9–20:
R
R
R
R
(1) “R” indicates that the instruction is required to be executed before the next instruction, “O” indicates the optional instruction, “Rc” indicates
the recommended instruction, and “NA” indicates that the instruction is not allowed to be executed in this mode.
(2) AP configuration is for Cyclone III devices only.
In AS or AP configuration schemes, the ACTIVE_DISENGAGEinstruction puts the active
configuration controllers into idle state. If a successful JTAG programming is
executed, the active controllers are automatically re-engaged after user mode is
reached using JTAG programming. This causes the active controllers to transition to
their respective user mode states.
If JTAG programming fails to get the Cyclone III device family to enter user mode and
re-engage active programming, there are available methods to achieve this for the AS
or AP configuration schemes:
■
When in the AS configuration scheme, you can re-engage the AS controller by
moving the JTAG TAP controller to the reset state or by issuing the ACTIVE_ENGAGE
instruction.
■
When in the AP configuration scheme, the only way to re-engage the AP controller
is to issue the ACTIVE_ENGAGEinstruction. In this case, asserting the nCONFIGpin
does not re-engage either active controller.
August 2012 Altera Corporation
Cyclone III Device Handbook
Volume 1
ALTERA [ ALTERA CORPORATION ]
