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RAMCHECK / RAMCHECK LX APPLICATION NOTE INN-8668-APN25


RAMCHECK Production Mode

INN-8668-APN25
--Created: 5-18-07
--Updated for RAMCHECK LX: 7-03-18

Production Mode automates the process of programming and verifying the SPD chip of memory modules on the production line. For DDR4 on RAMCHECK LX, Production Mode allows testing modules with blank SPD chips, provided the correct SPD data is loaded into the RAMCHECK's SPD Buffer.

Production mode offers four main operational functions:

Function Description SPD Data Source
Program + Verify RAMCHECK tests the module and at the end of the test (Basic or Extensive) it programs the SPD of the currently tested module with the master SPD data in the RAMCHECK's SPD Buffer. DUT's SPD is typically BLANK at the start of Basic Test, as it will be programmed with this function.
Verify Only Verify the entire SPD contents of the tested module to match the master SPD data (in the RAMCHECK's SPD Buffer). DUT's SPD must be programmed as it is compared to the RAMCHECK's SPD Buffer.
Match to Master Match only the main parameters section of the SPD of the tested module to the corresponding master SPD data (in the RAMCHECK's SPD Buffer). DUT's SPD must be programmed as it is partially compared to the RAMCHECK's SPD Buffer.
SPD from Buffer RAMCHECK LX test uses the SPD data from the SPD buffer and it totally ignores the DUT's SPD. For DDR4 modules, wrong SPD data in the RAMCHECK's SPD Buffer will disable the test (with various error messages). DUT's SPD is IGNORED and may be BLANK. Correct SPD data must be in the RAMCHECK's SPD Buffer.

The Master SPD Data

The master SPD data in the SPD Buffer can be obtained from a master module or from in your PC via the PC Communication program.

WARNING: WRONG SPD DATA ON A MEMORY MODULE MAY HALT THE PC ON WHICH IT IS INSTALLED! SPD PROGRAMMING SHOULD BE DONE ONLY BY ADVANCED USERS. ALWAYS KEEP BACKUP FILES!


Overview of Production Mode Functions

Program + Verify: This function performs the main goal of production mode - programming and verifying the blank SPD of the tested modules in accordance with the master SPD data. At the start of the Basic Test, the structure of the currently tested module is verified to match the master SPD data. If the module's size does not match the master SPD data, a Production Mode Size Error aborts the test. The offending size parameters are clearly displayed. The module's SPD can be programmed either at the end of Basic Test or at the end of the Extensive Test, based on your selection during Production mode setup. Please note that you must enable SPD Programming prior to the activation of the "Program + Verify" operation mode.

Verify Only: This function compares the entire contents of the DUT's SPD Serial EEPROM (all 256/512 Bytes) to the master SPD data stored in the RAMCHECK's SPD buffer. If it detects a mismatch, the RAMCHECK will give you an SPD verifying error at the end of Basic Test. Successful verifications are recorded in the Test Log.

Do not confuse the Verify Only function with the SPD Warning Messages explained in RAMCHECK Application Note 9 which compares the structure of the DUT as tested by the RAMCHECK with the SPD data on the DUT itself.

Match to Master: This function performs at the start of Basic Test and is intended to verify that the DUT has the same size and main SPD parameters like the master SPD data. If a module uses the SPD to record extra information like the serial number, it may still pass the Match to Master test, unlike the Verify Only function which fails any mismatch between the DUT's entire SPD and the master SPD data.

Match to Master includes two quick phases. The first phase verifies five key structure parameters as measured by the RAMCHECK with the corresponding structure bytes in the master SPD data. The second phase runs a complete verification of ONLY the first 32 bytes of the DUT's SPD. Both phases produce detailed error messages if they detect a mismatch. If the first phase detects a mismatch, its error report returns you to Standby mode. Therefore, the second phase is run only once the first phase can pass.

SPD from Buffer: This function allows RAMCHECK LX to test modules with blank SPD chips, provided the RAMCHECK's SPD Buffer is loaded with the correct SPD data for the tested module. In particularly, this function is useful to test DDR4 modules with blank SPDs, that otherwise will fail the RAMCHECK LX test (without the SPD data that must be used to configure the tester).

SPD Programming Setting for Production Mode

Please Note that only the "Program + Verify" function must have SPD programming enabled. The DUT's SPD must have a blank SPD. The "Verify Only" and "Match to Master" functions DO NOT ALTER the DUT's SPD and therefore can be run with RAMCHECK SPD Programming mode disabled.

Production Mode Setup

To select the function from above that you want to enable you must go to the Production Mode menu by turning the RAMCHECK on and wait until it cycles through its boot up sequence and displays the Start / Standby Screen. Next follow this key sequence:


A warning message will pop up regarding SPD Programming. This message is intended for those who plan to re-program the SPD, after about 5 seconds the message will disappear on its own and automatically go to the next menu, or you can expedite it by simply pressing the "ESC" key to advance to the next menu.

SPD Programming warning

In the following SPD menu, Press F1 for Production Mode, by default "DISABLED" should be displayed:

Production Mode disabled

Pressing F5 will go forward through the four options in the following order, "DISABLED" --> "PROGRAM + VERIFY" --> "VERIFY ONLY" --> "MATCH TO MASTER" "SPD FROM BUFFER". Pressing F2 will go back through the same list.

NOTE: You must have the RAMCHECK's SPD Programming enabled to select "PROGRAM + VERIFY" function.

After selecting the desired Production Mode function, you must select the source for the master SPD data. The menu provides you with three choices:

Production Mode disabled

"USE MASTER MODULE" - This is the only option that does not require the PC and the RAMCHECK PC Communications software. With this option enabled the RAMCHECK will prompt you for a master module when you start the Basic Test. Insert your Master Module with the SPD data you want to save to RAMCHECK's buffer into the RAMCHECK's test socket. Next press F4 for "Select Viewer", then F3 for "SPD Management". Select F1 to "Read Buffer" in order to copy the contents of the SPD from the master module to the buffer of the RAMCHECK. Press the ESC key a few times to go back to standby mode. Remove the module from the test socket, making sure that it is labeled as "Master Module" and put it in a safe place.

Production Mode disabled

"PC SPD FILE-Man" - In this option, you require the PC and RAMCHECK PC Communications software to send the master SPD data to the RAMCHECK's internal buffer. "Man" stands for manual and it means that you need to manally activate the transfer of the SPD file data from the PC.

Production Mode disabled

"PC SPD FILE-Auto" - In this option, your RAMCHECK must be connected to the PC and the SPD file is automatically loaded to RAMCHECK.

For more information on these two options please consult the Help Menu of the RAMCHECK's PC communications software.

"PROGRAM AT" SETUP

If you selected the "Program + Verify" function, setup will ask you if you want to perform the SPD programming on the DUT after Basic Test or after the successful completion of the much longer Extensive Test.

Production Mode Operation

PROGRAM + VERIFY

The master SPD Buffer data must be set once RAMCHECK is turned on. Press F1 to start the Basic Test. If the Buffer is empty you will get a message similar to the following:

Empty buffer

Once the Basic Test or the Extensive Test is completed the master SPD data in RAMCHECK's internal buffer will be automatically programmed into the DUT's SPD. The programmed SPD is then quickly verified.

As a precaution, the RAMCHECK automatically compares certain key bytes of the SPD data in RAMCHECK's internal buffer with the size and structure of the DUT as tested by the RAMCHECK. If they do not match, the test is aborted with an error message indicating the mismatch between the DUT and the SPD data in RAMCHECK's internal buffer.

Once the test is completed and the DUT successfully programs simply remove the DUT from the RAMCHECK and insert another to repeat the above process. The RAMCHECK will always keep the same SPD data in its internal buffer unless it is edited by the user, or the RAMCHECK is turn off then on again causing the internal buffer to be erased.

VERIFY ONLY

The master SPD data must be set once RAMCHECK is turned on. Press F1 to start the Basic Test. The Verify feature automatically compares the structure of the DUT as tested by the RAMCHECK with the master SPD data saved in RAMCHECK's internal buffer. The Verify feature compares five bytes listed below (actual SPD byte number changes based on DDR4/DDR3/DDR2/DDR1 module type):



If it finds any mismatch between any or all of the five bytes listed above it will automatically halt the test.

At the end of Basic Test, the entire SPD data of the DUT is compared with the master SPD data. Successful comparison is promptly logged in the Test Log. Failed comparison will stop the test and display an error message displaying the mismatch so you won't prematurely program incorrect structure data to the DUT. If you do not need to program but want to compare the SPD data saved in RAMCHECK's internal memory with the structure of any DUT, you can simply disable Programming Mode by using the key sequences above but select F2 for Programming Mode instead. To disable the Production Verify feature simply disable Production mode by using the key sequence above.

MATCH TO MASTER

The master SPD data must be set once RAMCHECK is turned on. Press F1 to start the Basic Test.

At the start of Basic Test, the structure of the DUT as tested by RAMCHECK is compared with the corresponding bytes in the master SPD data. If there is a mismatch, a detailed error is reported. This is similar to the "VERIFY ONLY" function described above. If the structure match, RAMCHECK continues with comparison of the first 32 bytes of the DUT's SPD (which contains most of the critical information about the DUT speed and structure) to the master SPD data. Any mismatch error with details aborts the test if needed. Please note that both comparison are extremely fast and occurs within the first second of Basic Test. If the DUT structure and critical 32 bytes match, the test completes normally.

SPD FROM BUFFER

This function allows module makers to test modules with blank SPD chips while getting the SPD data (reguired for the tested modules) from the RAMHCECK's SPD buffer instead of directly from the test modules. Therefore, SPD FROM BUFFER allows you to test DDR4 module with blank SPD chips, provided the proper master SPD data is loaded onto the RAMCHECK's SPD buffer.

Before testing a module with a blank SPD chip, make sure to load the RAMCHECK's SPD buffer with the correct SPD data correponding to the same module. Like Motherboards, RAMCHECK LX depends heavily on the SPD data to test the DDR4 modules. You can load the RAMCHECK's SPD buffer by taking the same module with a correctly programmed SPD chip as the master module. Then, RAMCHECK will test the same modules even if they have blank SPD chips.

When you try to test a different DDR4 module (while the RAMCHECK's SPD Buffer holds the SPD data for another module), RAMCHECK LX test will fail with various messages, since the tester is configuring itself for a different module!

While you use the SPD FROM BUFFER function and already stored the SPD data from the master module onto the RAMCHECK's SPD buffer, you may want to check that a currently installed module is blank. Since reading the blank SPD will replace the RAMCHECK's SPD Buffer contents, any attempt to read SPD while the buffer is loaded results with follwing message reminding you that you will later need to restore the master SPD data:

Empty buffer

If you abort, the master data remains in the RAMCHECK's SPD Buffer. If you continue with reading the SPD, the SPD Buffer data will be altered and you will need to reload the master data onto the RAMCHECK's SPD Buffer.


MANUAL SPD PROGRAMMING WHEN PRODUCTION MODE IS ON:

You can still program the SPD manually while in standby mode. Press F4 for "Select Viewer", then F3 for "SPD Management", then F3 to "Program". Please note: Programming Mode must be enabled to manually program, please see SPD Management for further details.



CONTACTING OUR TECHNICAL SUPPORT DEPARTMENT

For more information, please call us at 1-281-879-6226 M-F 9:00-5:00 US Central Time, or send your e-mail to support@innoventions.com, or fax your message to 1-281-879-6415. Please remember to include your phone and e-mail.