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Changing the Static Source Address, Manufacturer ID and Product ID fields is only possible via protected data access as described below to prevent unauthorized
modification.
For security reasons, the telegram sequence counter cannot be written or reset by any mechanism.
6.6 Protected Data
The following items are located in the protected data area:
■ Source Address Write register
This 4 byte register is used to update the lower 4 byte of the Static Source Address, see chapter 6.6.3
■ Product ID Write register
This 8 byte register is used to update the Product ID, see chapter 6.6.5
■ Manufacturer ID Write register
This 4 byte register is used to update the Manufacturer ID, see chapter 6.6.5
■ Security Key Write register
This 16 byte register is used to update the security key used by 03925, see chapter 6.6.4
■ Optional Data register
This 4 byte register contains optional data that can be transmitted as par t of all data telegrams, see chapter 4.6. Optional Data 0 is sent first, Optional Data 3 last.
■ Configuration register
This 1 byte register is used to configure the functional behavior of 03925, see chapter 6.6.7
■ Custom Variant register
This 1 byte register is used to configure the transmission behavior of 03925, see chapter 6.6.8
■ Custom Radio Channel registers (CH_REG1, CH_REG2 and CH_REG3)
These 1 byte registers are used to configure the radio channels in custom transmission mode of 03925, see chapter 6.6.9
■ Custom NFC Data
03925 reser ves 64 byte for customer-specific NFC data, see chapter 6.6.10
6.6.1 PIN Code
Protected data access is only possible after unlocking the configuration memory with the correct 32 bit PIN code. By default, the protected area is locked and
the default pin code for unlocking access is 0x0000E215.
The default pin code shall be changed to a user-defined value as par t of the installation process. This can be done by unlocking the NFC interface with the old
PIN code and then writing the new PIN code to page 0xE5 as described in chapter 6.3.1.
6.6.2 Configuration of product parameters
03925 allows no direct modification of the following parameters:
■ Static Source Address
■ Product ID
■ Manufacturer ID
■ Security Key
In order to modify these parameters, the user has to write the new value into specific registers (Source Address Write, Product ID Write, Manufacturer ID Write
and Security Key Write) in the protected data area and set the according Update flag in the Configuration register.
After that, the user has to push and release the energy bar of the 03925 module.
6.6.3 Source Address Write register
The Source Address Write register is 4 byte wide and can be used to modify the lower 32 bit of the 03925 Static Source Address. The upper 16 bit of the 03925
Static Source Address are always fixed to 0xE215 to identify the device t ype.
In order to do change the lower 32 bit of the Static Source Address, follow these steps:
1. Write new source address into the Source Address Write register
2. Set the Update Source Address flag in the Configuration register to 0b1
3. Actuate (press and release) the energy bar of 03925
03925 will determine that it should modify the Static Source Address based on the setting of the Update Source Address flag and copy the value of the Source
Address Write register to the lower 32 bit of the Source Address register.
After successful execution, 03925 will clear the Update Source Address flag to 0b0.
6.6.4 Security Key Write register
The Security Key Write register is 16 byte wide and contains the device-unique random security key.
The factor y programmed key can be replaced with a user defined key by following these steps:
1. Write new security key into the Security Key Write register
Note that for security reasons, setting the Security Key to the following values is not possible:
• 0x00000000000000000000000000000000
• 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF
If the Security Key Write register is set to one of these values then no update of the Security Key will occur.
NFC interface