TDC-GP21 datasheet(40/91 Pages) AMSCO

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TDC-GP21

acam messelectronic gmbh - Friedrich-List-Str.4 - 76297 Stutensee - Germany - www.acam.de

3-15

3.3

EEPROM

The TDC-GP21 has a 7x32 bit EEPROM. This EEPROM can be used to store the

configuration data together with the ID or version number. Only the following three actions

are possible:



Write configuration register content into the EEPROM



Transfer the EEPROM content into the configuration registers



Compare the configuration registers‘ content with the EEPROM content

Besides the ID it is not possible to read back the EEPROM. This gives customers the

possibility to program the chips by themselves and prohibit other to read back the

configuration.

For verification it is possible to compare the configuration register may be compare with

the EEPROM. Bit EEPROM_eq_CREG in the status register indicates whether the content is

equal or not.

The EEPROM has an internal error correction (Hamming code). It is possible



to detect and correct single bit errors,



to detect multi-bit errors without correction

Errors are indicated in the status register, bits EEPROM_Error (single bit) and

EEPROM_DED (double error detection).

*****With each read access/compare to the EEPROM the error bit is checked. In case

a single bit error is detected a refresh cycle is started automatically and the data is

restored.

The data retention of the EEPROM is > 10 years @ 85 °C without single or multiple

errors. With regular Compare_EEPROM commands (e.g. once per month) the data

retention can be extended unlimited.

Important Note:

If values are to be stored in the EEPROM it is mandatory to ensure that NO measurement is

running (neither ToF nor temperature nor calibration measurements). During measurement a

write access to the EEPROM is not permitted. The write access to the EEPROM takes about

300 ms. With no consideration, the EEPROM may be written with incorrect values. It may even

happen that adjustment values are overwritten which prevents proper operation of the TDC.

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TDC-GP21 Datasheet(PDF) 40 Page - ams AG