2500_Users_Manual.pdf - 第89页

Task s and Ki ts 3-14 ProMa ster 25 00 U ser Ma nual • Serial Vector Test — The 2500 applies test vectors to the device inputs in parallel . If the PLD design requires certain input pins to be applied before others, the …

Tasks and Kits

ProMaster 2500 User Manual 3-13

TaskLink displays the Logic Device Parameters dialog box with these

main options:

•

Verify Options

— Select one option from the three offered.

•

Fuse verify only

— Compares the fuses programmed in the logic

device with the pattern in the 2500’s RAM. No structured test

vectors are applied to the device even if they were downloaded in

the JEDEC data file.

•

Functional test only

— Verifies the programmed device using the

structured test vectors downloaded with the JEDEC data file. The

fuses in the device are not checked. This is useful when the devices

have had their security fuse programmed so that the fuse pattern in

their main array can no longer be read by the programmer. Vectors

written for the device will confirm that the device is functioning

correctly if all vectors pass.

•

Fuse verify

and

functional test

(default)—Verifies the

programmed device by comparing the device fuses against the

fuses in RAM. If the device passes, the test vectors are applied to

the device. If all the fuses verify and the vectors pass, the device is

labeled and placed in the pass output tube.

•

Vector Options

—

Select any combination of these three options to

change the way logic test vectors are applied to your device during

the verify cycle. These test vector options may improve the yield of

devices that pass fuse verify but fail test vectors. Certain PLD Tasks

may experience a higher failure rate when test vectors are run. These

failures are usually a combination of conditions in the design (as

defined in the JEDEC file), the internal characteristics of the device,

and the way the 2500 applies vectors. These test vector options affect

the way the 2500 applies the file’s test vectors to the device in an

attempt to improve the number of devices that pass test vectors.

•

Compensated Vectors

— Some PLD designs create combinatorial

latches on registered outputs and may fail test vectors even though

the devices have been programmed correctly. This is most often

due to a combination of factors including the specific PLD design,

the device’s internal hardware characteristics, and the

programming electronics in the 2500. If this parameter has been

disabled and a large number of combinatorial output devices are

failing test vectors, selecting Compensated Vectors may improve

the yield. This parameter is enabled by default in TaskLink.

•

High-speed Drivers

— Some PLD designs, when implemented in

certain high-speed PLDs, will fail test vectors even though the

device programmed correctly and functions correctly in-circuit.

The High-speed Drivers option (which is enabled by default)

applies the vector inputs to the device at a higher speed, using a

higher current drive.

Note: Because this option is enabled by default, be careful how you write your

drivers. If the JEDEC file test vectors have not been written correctly, this

higher current applied to a bi-directional input pin might damage some

devices.

Tasks and Kits

3-14 ProMaster 2500 User Manual

•

Serial Vector Test

— The 2500 applies test vectors to the device

inputs in parallel. If the PLD design requires certain input pins to

be applied before others, the JEDEC standard states that the test

vectors must be written to enforce that particular order. When this

option has been selected, the 2500 applies the vector inputs starting

with device pin 1 and continuing in numeric order to the last input.

This option will not harm the device and should be used as a

troubleshooting tool when a large number of devices are passing

fuse verify but failing test vectors. It is not enabled by default.

•

DIP/LCC vector translation

— In some instances the test vectors in

the JEDEC file were written for a DIP device but will be used to verify

a PLCC part. When this translation option is selected, the 2500

automatically translates the DIP test vectors during the download

into the correct format to test the PLCC/LCC part.

Data Sumcheck

This optional parameter, when selected, will check the sumcheck at the

end of the file transfer with the sumcheck entered in this Task field. For

additional information on this parameter, see page 3-18.

Creating a Task for a Memory Device

Creating a Task for a memory device requires that you define the same

mandatory fields used in the logic device Task (see page 3-4). Entering

the parameters for these mandatory fields follows the same procedures

that you used for the logic devices. The following mandatory parameters

must be defined before a Memory Task will run.

• Define one or more

Device(s)

•Select

Data Source

•Select

Data File

and

Translation Format

• Select one or more

Process(es)

•Select

< More... >

and

Handling/Labeling Parameters...

(Package

type, Pin 1 Orientation, Print Density, and Text).

Figure 3-10

Memory Device Task

Tasks and Kits

ProMaster 2500 User Manual 3-15

Selecting a

Translation Format

Selecting the translation format requires matching the data file format on

your PC disk with one of the more than 35 formats supported by the 2500.

Refer to the list of formats on the TaskLink screen by pressing

from the

Translation Format

field on the

Edit Task

dialog box (see Figure 3-10).

Note: Consider high-speed download compatibility when you choose a format.

To identify an unknown format, refer to Appendix D for a description

and example of each data format supported by the 2500.

Other Memory

Parameters

From the Edit Task screen, select

<MORE>

and then

Memory

Parameters...

. TaskLink displays the

Memory Device Parameters

dialog

box with options described in the following sections.

TaskLink supports a variety of Data I/O programmers. Some of the

commands and options displayed on TaskLink’s menus (

Administrator

mode

only) are intended to be used with other products and are not used

in the operating environment of the 2500. Information on these

commands is available by pressing

to invoke TaskLink’s online Help.

Only the commands used with the 2500 are described below.

Word Width

Word width is defined as the word size of the device being programmed.

In most cases this value defaults to the number of data bits at each

address in the device and therefore it is not changed.

Figure 3-11

Memory Parameters Dialog Box