AS39513 datasheet(46/108 Pages) AMSCO

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[v1-10] 2018-Apr-25

AS39513 − Detailed Description

Factory Access Region

The Factory access region is for factory-only calibration

parameters and control settings, as well as password storage

and memory lock bits. The region is not accessible through the

RFID interface. Attempts to write to this region through the RFID

interface will generate a password error. Reads through the

RFID interface will simply read 0x00 for each byte with no error.

The Factory access regions are readable through the SPI, but

are only writeable if Factory access is active.

Factory access is made active by writing a special hard-coded

Factory access password using the SPI direct command “Factory

Access”. If Factory access is not open, SPI writes to Factory access

area will simply be ignored.

There are three sub-regions of Factory access.

The first sub-region is the EEPROM region from address 0x440

through 0x47F. All values in this region are readable and

writable via the SPI with the correct access.

The second sub-region of Factory access is the mirrored

registers. It is for EEPROM parameters that are read and copied

into registers at startup. This region is from address 0x640

through 0x67F. All values in this region are write-only (with the

correct access). All bytes in this region will read back as 0x00

(with no error).

The third sub-region of Factory access is the volatile registers.

These registers are used for factory level parameters that are

not duplicated in the EEPROM and require access through the

memory map. This region goes from address 0x740 through

0x77F. All values are writeable with the correct access. No

addresses in this region are readable; they all read back as 0x00

with no error.

The remaining sections in this chapter describe the parameters

in the System and Factory regions of the memory map, one

16-byte page at a time.

AS39513 Datasheet(PDF) 46 Page - ams AG