Security Operations
Antitearing
In the event of a power loss during a write cycle, the integrity of the device’s stored data
may be recovered. This function is optional: the host may choose to activate the
antitearing function depending on application requirements. When antitearing is active,
write commands take longer to execute since more write cycles are required to
complete them. Data writes are limited to 8-byte pages when antitearing is active.
Data is written first to a buffer zone in EEPROM instead of to the intended destination
address, but with the same access conditions. The data is then written to the required
location. If this second write cycle is interrupted due to a power loss, the device will
automatically recover the data from the buffer zone at the next power-up.
Password Verification
Authentication Protocol
Passwords may be used to protect user zone read and/or write access. When a
password is presented using the Check Password command, it is memorized and active
until power is removed unless a new password is presented or a valid DESELECT or
IDLE command is received. Only one password is active at a time, but write passwords
also give read access.
The access to a user zone may be protected by an authentication protocol in addition to
password dependent rights. Passwords are encrypted in authentication mode.
The authentication success is memorized and active as long as the chip is powered,
unless a new authentication is initialized or a valid DESELECT or IDLE command is
received. If the new authentication request is not validated, the card loses its previous
authentication and it must be presented again. Only the last request is memorized.
Encryption
The data exchanged between the card and the reader during Read, Write, and Check
Password commands may be encrypted to ensure data confidentiality.
The issuer may choose to protect the access to a user zone with an encryption key by
settings made in the configuration memory. In that case, activation of the encryption
mode is required in order to read/write data in the zone.
The encryption activation success is memorized and active as long as the chip is
powered, unless a new initialization is initiated or a valid DESELECT or IDLE command
is received. If the new encryption activation request is not validated, the card will no
longer encrypt data during read operations nor will it decrypt data received during write
or Check Password operations.
Checksum
The PICC implements a data validity check function in the form of a checksum. The
checksum may function in standard or cryptographic mode. In the standard mode, the
checksum is optional and may be used for transmission error detection. The
cryptographic mode is more powerful since it provides data origin authentication
capability in the form of a Message Authentication Code (MAC). To write data to the
device, the host is required to compute a valid MAC and provide it to the device. If after
an ingoing command the device computes a MAC different from the MAC transmitted by
the host, not only is the command abandoned but the cryptographic mode is also reset.
A new authentication is required to reactivate the cryptographic mode.
Initial Device
Programming
CryptoRF is delivered with all security features disabled. To program the polling
response or enable the security features of CryptoRF the device must be personalized
by programming several registers. This is accomplished by programming the
configuration memory using simple write and read commands.
6
AT88SC0104CRF
5021CS–CRRF–12/06
5秒后页面跳转
STM32H743技术深度剖析与应用案例探索
LM321中文资料解析：引脚功能介绍、技术特点、技术特性分析
74HC14芯片资料介绍：性能特性分析、引脚介绍
LM1875芯片手册：功放参数分析、引脚说明、电路设计要点
微信公众号
抖音公众号
浙公网安备 33010502006866号 浙ICP备10014259号-119
营业执照ICP证
数据手册
如果您发现信息不准确，
