- 您现在的位置：买卖IC网 > Sheet目录474 > MAX66000K-000AA+ (Maxim Integrated)IC RFID UID 64BIT TYPE B KEY FOB
ISO/IEC 14443 Type B-Compliant
64-Bit UID
Logically, the DESELECT command is a special case of
the S-block of the block transmission protocol, as
defined in part 4 of the ISO/IEC 14443 standard. The
MAX66000 responds to a DESELECT command if the
CID in the request and the CID in the device match. If
the DESELECT request does not include a CID, the
MAX66000 only responds to the request if its CID is
0000b.
The response frame to the DESELECT command is
identical to the request frame. The slave returns the
same data that it had received, confirming that the
slave addressed in the request has been transitioned to
the HALT sate.
Anticollision Examples
Probabilistic Anticollision
The master starts the anticollision process by issuing an
REQB or WUPB command. The WUPB command
involves any slave in the field with a matching AFI code.
The REQB command performs the same function, but is
ignored by slaves in the HALT state. Both commands
include the parameter N, which according to Table 2 is
used to set the probability of an ATQB response to 1/N.
If N = 1, all participating slaves respond with the ATQB
response. If N is greater than one, then each slave
selects a random number R in the range of 1 to N. If a
slave happens to choose R = 1, then it responds with
ATQB. If R is greater than 1, then the slave waits for
another REQB or WUPB command, which causes the
participating slaves to choose a new random number R.
The ATQB response contains a field named PUPI,
which is used to direct commands to a specific slave
during the anticollision process. When the master
receives an ATQB response, it should issue a matching
HLTB command to halt the slave or issue a matching
ATTRIB command to assign a CID and place the slave
in the ACTIVE state. If this is not done, the slaves con-
tinue to participate in the anticollision process. A slave
in the ACTIVE state ignores all REQB, WUPB, SLOT-
MARKER, ATTRIB, and HLTB commands, but responds
to the DESELECT command.
An ATQB response received with a CRC error indicates
a collision because two or more slaves have responded
at the same time. With probabilistic anticollision, the
master must issue another REQB command to cause
the slaves in the field that are not in the HALT or
ACTIVE state to select a new random number R. If one
of the slaves has chosen R = 1, it responds with ATQB.
A REQB without ATQB response does not guaran-
tee that all slaves in the field have been identified.
Figure 29 shows an example of the time-slot anticolli-
sion, assuming that there are four slaves in IDLE state in
the field. The process begins with the master sending
an REQB request with N = 1, which forces all slaves to
respond with ATQB, resulting in a collision. Knowing that
slaves are present, the master now sends REQB with
N = 8. This causes all slaves to select a random number
in the range of 1 to 8. Only the slave that has chosen R
= 1 responds, which is slave C in the example. Knowing
that there are more slaves in the field, the master contin-
ues issuing REQB commands, which in the example,
eventually identifies all slaves. Due to its statistical
nature, probabilistic anticollision is less likely to find
every slave in the field than the time-slot anticollision.
TESTING FOR SLAVES
ATTEMPT 1
ATTEMPT 2
ATTEMPT 3
ATTEMPT 4 ATTEMPT 5
ATTEMPT 6
MASTER
SLAVE A
SLAVE B
REQB
(N = 1)
ATQB
ATQB
REQB
(N = 8)
(R = 3)
(R = 6)
REQB
(N = 8)
(R = 7)
(R = 4)
REQB
(N = 8)
(R = 1) ATQB
(R = 8)
REQB
(N = 8)
(R = 3)
(R = 8)
REQB
(N = 8)
(R = 6)
(R = 5)
REQB
(N = 8)
(R = 8)
(R = 1) ATQB
SLAVE C
ATQB
(R = 1) ATQB (R = 8)
(R = 2)
(R = 4)
(R = 3)
(R = 4)
SLAVE D
ATQB
(R = 2)
(R = 1) ATQB (R = 5)
(R = 8)
(R = 4)
(R = 2)
Figure 29. Probabilistic Anticollision Example
16
______________________________________________________________________________________
发布紧急采购，3分钟左右您将得到回复。
相关PDF资料
MAX66020K-000AA+
IC RFID UID 1KB TYPEB MEM KEYFOB
MAX66040K-000AA+
ISO CARD SECURE MEMORY
MAX6605MXK/V+T
IC TEMP SENSOR ANLG LP SC70-5
MAX6608IUK+T
IC TEMP SENSOR ANLG SOT23-5
MAX66100K-000AA+
IC RFID UID 64BIT TYPE B KEY FOB
MAX6611AUT+T
IC TEMP SENS LOW PWR SOT23-6
MAX66120K-000AA+
IC RFID UID 1KB TYPEB MEM KEYFOB
MAX6612MXK+T
IC TEMP SENSOR ANLG SC70-5
相关代理商/技术参数
MAX66000K-00AA+
制造商:Maxim Integrated Products 功能描述:ISO/IEC 14443 TYPE B-COMPLIANT 64-BIT, UID FOB - Rail/Tube
MAX66020K-000AA+
功能描述:RFID应答器 ISO/IEC 14443 Type B Comp 1Kb Mem Fob
RoHS:否 制造商:Murata 存储容量:512 bit 工作温度范围:- 40 C to + 85 C 安装风格:SMD/SMT 封装 / 箱体: 封装:Reel
MAX66020K-00AA+
制造商:Maxim Integrated Products 功能描述:ISO/IEC 14443 TYPE B-COMPLIANT 1KB MEMORY FOB - Rail/Tube
MAX6602UE9A+
功能描述:板上安装温度传感器 5Ch Precision Temperature Monitor RoHS:否 制造商:Omron Electronics 输出类型:Digital 配置: 准确性:+/- 1.5 C, +/- 3 C 温度阈值: 数字输出 - 总线接口:2-Wire, I2C, SMBus 电源电压-最大:5.5 V 电源电压-最小:4.5 V 最大工作温度:+ 50 C 最小工作温度:0 C 关闭: 安装风格: 封装 / 箱体: 设备功能:Temperature and Humidity Sensor
MAX6602UE9A+T
功能描述:板上安装温度传感器 5Ch Precision Temperature Monitor RoHS:否 制造商:Omron Electronics 输出类型:Digital 配置: 准确性:+/- 1.5 C, +/- 3 C 温度阈值: 数字输出 - 总线接口:2-Wire, I2C, SMBus 电源电压-最大:5.5 V 电源电压-最小:4.5 V 最大工作温度:+ 50 C 最小工作温度:0 C 关闭: 安装风格: 封装 / 箱体: 设备功能:Temperature and Humidity Sensor
MAX6603ATB
制造商:Maxim Integrated Products 功能描述:DUAL-CHANNEL PLATINUM RTD-TO-VOLTAG - Rail/Tube
MAX6603ATB+
制造商:Maxim Integrated Products 功能描述:RTD TO VOLT SGNL CONDITIONER 10TDFN EP - Rail/Tube
MAX6603ATB+T
功能描述:板上安装温度传感器 RTD-to-Voltage Signal Conditioner RoHS:否 制造商:Omron Electronics 输出类型:Digital 配置: 准确性:+/- 1.5 C, +/- 3 C 温度阈值: 数字输出 - 总线接口:2-Wire, I2C, SMBus 电源电压-最大:5.5 V 电源电压-最小:4.5 V 最大工作温度:+ 50 C 最小工作温度:0 C 关闭: 安装风格: 封装 / 箱体: 设备功能:Temperature and Humidity Sensor