IEEE 1532 (ISC)

June, 2006

Alexander Brill

Reminder - IEEE

Institute of Electrical and Electronics Engineers

It is the world's leading professional association for the advancement of technology.

Organization of engineers, scientists and students involved in electrical, electronics, and related fields. It is a publishing house and standards-making body.

IEEE is a non-profit organization.

IEEE 1532 (ISC)

IEEE Standard for Boundary-Scan-based In System Configuration of Programmable Devices

Neil G. JacobsonXilinx, Inc.

San Jose, CA, USAneil.jacobson@xilinx.com

The development of IEEE Std 1532

April of 1996: A group of Programmable Device vendors

and users discussed the possibility of standardizing the programming process for these devices.

This work received the support of the IEEE Std 1149.1 Working Group.

July of 1998: IEEE Std 1532 is formally initiated.

IEEE 1532 (ISC)

Devices that implement this standard shall first be compliant with IEEE Std 1149.1-2001 , which is used for testing purposes.

A device, or set of devices, implementing this standard may be programmed (written) , read back, erased, and verified, singly or concurrently, with a standardized set of resources.

ISC - In-System Configuration

This standard allows the programming of one or more compliant devices concurrently, while mounted on a board or embedded in a system.

The standard specifies a common software platform for programming a variety of device types, including memory devices and programmable logic devices (PLDs).

In-System Configuration

Devices may be programmed after they have been attached to the board, via a physical and logical protocol:

Physical protocol: IEEE Std 1149.1 Test Access Port (TAP) pins,

Logical protocol: New instructions added to the IEEE Std 1149.1 instruction set.

What is in IEEE 1532?

Mandatory and optional programming instructions that define a standard methodology for accessing and configuring programmable devices.

The IEEE 1149.1 Test Access Port may be used for configuration activities.

Data description format

Extensions to Boundary-Scan Description Language (BSDL)

IEEE Standard 1532 BSDL Files

The PLD manufacturer generates an IEEE Standard 1532 BSDL file for each conforming device.

The IEEE Standard 1532 extensions define a 1532-specific package and framework of attributes that describe the programming algorithms for the corresponding PLD.

These extensions are compatible with the original IEEE Standard 1149.1-2001 BSDL syntax.

An IEEE Standard 1532 BSDL file can be identified using the STD_1532_2002 package.

Use STD_1532_2002.all; -- 1532 BSDL Extension for ISC devices

IEEE Standard 1532 Data Files

The IEEE Standard 1532 data file is a textfile format.

The first section in the file is the header,consisting of the following information:

• Header• Version STD_1532_2001

• Creation date• Creator

IEEE Standard 1532 Data Files(2)

The remainder of the data file contains data for the various named data sections, as described in the device’s 1532 BSDL file.

Device Configuration

JTAG State Machine

Operational modes defined by 1149.1:

1532 System Modal States

The standard defines four system modal states:

Unprogrammed Operational ISC Accessed ISC Complete

1532 System Modal States

Device Configuration

In order to configure a device, a sequence of ISC instructions and data are loaded into the device.

ISC operations are always executed when the TAP controller is transitioned to the Run-Test/Idle State.

Device Configuration – steps(1/4)

1. Load ISC-ENABLE instruction2. Load data associated with ISC-ENABLE

instruction3. Transition to and stay in the

Run-Test/Idle TAP controller state for the prescribed amount of time.

----------------------------------------------------------------

This completes the device’s preparation to begin performing ISC operations.

Device Configuration – steps(2/4)

4. Load the ISC-ERASE instruction

5. Load data associated with the ISC-ERASE instruction.

6. Transition to and stay in the Run-Test/Idle TAP controller state for the prescribed amount of time.

---------------------------------------------------------------

This erases the programmed contents of the device’s configuration memory.

Device Configuration – steps(3/4)

7. Load the ISC-PROGRAM instruction8. Load the configuration data associated with the ISC-PROGRAM instruction.9. Transition to and stay in the Run-Test/Idle TAP controller state for the prescribed amount

of time.10. Repeats steps 8 and 9 --------------------------------------------------------------- Configuration memory is loaded with the

program.

Device Configuration – steps(4/4)

11. Load the ISC-DISABLE instruction12. Transition to and stay in the Run-Test/Idle

TAP controller state for the prescribed amount of time.

-------------------------------------------------------------- The device is now operational and the

system pins take on their programmed behaviors!!!

Conclusion

What can we do?

configure reconfigureread back verify erase

AFTER the device has been installed!!

What do we save?

Concurrent programming

significant programming time efficiencies

The total programming time for a board or system is often reduced from the sum of the times for programming each device individually to simply the longest time it would take to program any one device.

Testing

The ISC devices also contain testability circuitry compliant with IEEE Std 1149.1.

Everybody Use It:

The End