Chapter 3: JTAG and In-System Programmability
Referenced Documents
3–7
Real-Time ISP
For systems that require more than DC logic level control of I/O pins, the real-time
ISP feature allows you to update the CFM block with a new design image while the
current design continues to operate in the SRAM logic array and I/O pins. A new
programming file is updated into the MAX II device without halting the original
design’s operation, saving down-time costs for remote or field upgrades. The updated
CFM block configures the new design into the SRAM upon the next power cycle. It is
also possible to execute an immediate configuration of the SRAM without a power
cycle by using a specific sequence of ISP commands. The configuration of SRAM
without a power cycle takes a specific amount of time (t
CONFIG
). During this time, the
I/O pins are tri-stated and weakly pulled-up to V
CCIO
.
Design Security
All MAX II devices contain a programmable security bit that controls access to the
data programmed into the CFM block. When this bit is programmed, design
programming information, stored in the CFM block, cannot be copied or retrieved.
This feature provides a high level of design security because programmed data within
flash memory cells is invisible. The security bit that controls this function, as well as
all other programmed data, is reset only when the device is erased. The SRAM is also
invisible and cannot be accessed regardless of the security bit setting. The UFM block
data is not protected by the security bit and is accessible through JTAG or logic array
connections.
Programming with External Hardware
MAX II devices can be programmed by downloading the information via in-circuit
testers, embedded processors, the Altera
®
ByteblasterMV™, MasterBlaster™,
ByteBlaster™ II, and USB-Blaster cables.
BP Microsystems, System General, and other programming hardware manufacturers
provide programming support for Altera devices. Check their websites for device
support information.
Referenced Documents
This chapter references the following documents:
■
■
chapter in the
MAX II Device Handbook
chapter in the
MAX II
Device Handbook
chapter in the
MAX II Device
Handbook
chapter in the
MAX II Device
Handbook
■
■
ALTERA [ ALTERA CORPORATION ]
