參數(shù)資料
型號： MCP450SN
廠商： Microchip Technology Inc.
英文描述： 13.56 MHz Read/Write Passive RFID Device
中文描述： 13.56 MHz讀/寫無源RFID器件
文件頁數(shù)： 16/50頁
文件大?。?/td> 1172K
代理商： MCP450SN
MCRF450/451/452/455
DS40232H-page 16
2003 Microchip Technology Inc.
6.0
READ/WRITE ANTI-COLLISION
LOGIC
This section includes the anti-collision algorithm of the
device and consists of the Anti-collision/command
controller, the time slot generator and the time slot
counter.
6.1
Description of Algorithm
The read/write anti-collision algorithm is based on time
division multiplexing of tag responses. Each device is
allowed to communicate with the Interrogator in its time
slot only. When not in its assigned time slot, the device
remains in a nonmodulating condition. This enables the
Interrogator to communicate with other devices in the
same Interrogator field with fewer chances of data
collision.
Figure 6-1 shows the anti-collision algorithm flowchart,
which consists of four control loops. They are:
Detection, Processing, Sleeping and Reactivation
loops. All devices in the Interrogator’s RF field are
controlled by five different commands and internal
control flags.
The Interrogator commands are:
1.
Fast Read Request (FRR):
If the TF bit (bit 30
or Block 0) is cleared, the device responds only
to the FRR command. The FRR command
consists of five specially timed gap pulses (refer
to Figures 6-3 to 6-7). The position of the five
gap pulses in the given time span (1.575 ms)
determines the parameters of the command.
The command has three parameters: TCMAX,
TSMAX and Data transmission speed. The
details of these parameters will be discussed in
the following sections. If the device receives the
FRR command, it sends the FR response
and then listens for 1 ms (T
LW
) for a matching
code from the Interrogator.
2.
Fast Read Bypass (FRB):
This command is
used in the Reactivation loop and is only appli-
cable to a device with the FR bit (bit 31 in Block
0) cleared. The device responds with 64 bits of
data, which includes Block 1 data (32-bit Tag
ID), and then listens for 1 ms (T
LW
) for a match-
ing code from the Interrogator. The command
structure is the same as the FRR command: five
specially timed gap pulses (1.575 ms). The
command parameter (Figure 6-8) determines
the data rate (normal speed or fast speed) of
subsequent Interrogator commands.
3.
Matching Code 1 (MC1):
This command
consists of time calibration pulses (TCP)
followed by 1-of-16 PPM signals. It is used when
the device does not need any further process-
ing. This MC1 command causes a device, which
is in the detection loop, to enter the sleeping
loop.
4.
Matching Code 2 (MC2)
: The command
structure is the same as MC1: TCP followed by
1-of-16 PPM signals. The command is used
when the device needs further processing (read/
write). The device enters the processing loop if
it receives this command in the detection loop.
The MC1 and MC2 matching code command
consists of 12 bits or 3 symbols. The first 8 bits,
or the first two symbols, are selected from the
32-bit Tag ID. The next 4 bits, or the 3rd symbol,
determine the matching code type (3 bits) and a
parity bit (see
Section 6.2.3.6 “Calculation Of
Matching Code”
). The command lasts for
about 11.2 ms, including the TCP.
5.
End Process (EP):
This command consists of
the
time
reference
pulses
followed
by
1-of-16 PPM signals. The EP command causes
a device to exit the processing loop and enter
the sleeping loop.
6.1.1
DETECTION LOOP
If the FR bit (bit 31 of Block 0) is set, the device can
enter this loop in two ways, depending on the condition
of the TF bit (bit 30 of Block 0). They are:
1.
When the TF bit is cleared, the device enters
this loop and waits for a FRR command. This is
called the “Interrogator-Talks-First” (ITF) mode.
2.
When the TF bit is set, the device enters this
loop by transmitting the FR response without
waiting for an FRR command. This is called the
“Tag-Talks-First” (TTF) mode.
For case 1 above, the parameters of the FRR are:
Maximum number of time slots
(TSMAX = 1, 16, or 64),
Maximum transmission counter
(TCMAX = 1, 2, or 4),
Data transmission speed (Normal or Fast mode).
The purpose of the TSMAX and TCMAX parameters is
to acknowledge the device in the detection loop as fast
as possible. TSMAX represents the maximum number
of time slots between the end of the FRR command and
the beginning of the FR response. One time slot
(T
SLOT
) represents 2.5 ms. For example, TSMAX = 64
represents a maximum time delay of 160 ms before
sending the FR response. See
Section 6.3 “Time
Slot Generator”
for the calculation of actual time
delay. TCMAX represents the maximum number of FR
responses a device can send after an FRR command.
For example, TCMAX = 4 means the device can send
its FR response four times (after the FRR command)
for acknowledgment (matching code).
相關(guān)PDF資料
PDF描述
MCP450W 13.56 MHz Read/Write Passive RFID Device
MCP450WB 400000 SYSTEM GATE 1.8 VOLT FPGA - NOT RECOMMENDED for NEW DESIGN
MCP450WF 400000 SYSTEM GATE 1.8 VOLT FPGA - NOT RECOMMENDED for NEW DESIGN
MCP450X 13.56 MHz Read/Write Passive RFID Device
MCP451 13.56 MHz Read/Write Passive RFID Device
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MCP4531-103E/MS 功能描述:數(shù)字電位計 IC Sngl 7B V I2C POT RoHS:否 制造商:Maxim Integrated 電阻:200 Ohms 溫度系數(shù):35 PPM / C 容差:25 % POT 數(shù)量:Dual 每 POT 分接頭:256 弧刷存儲器:Volatile 緩沖刷: 數(shù)字接口:Serial (3-Wire, SPI) 描述/功能:Dual Volatile Low Voltage Linear Taper Digital Potentiometer 工作電源電壓:1.7 V to 5.5 V 電源電流:27 uA 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TQFN-16 封裝:Reel
MCP4531-103E/MS 制造商:Microchip Technology Inc 功能描述:Digital Potentiometer IC
MCP4531-104E/MS 功能描述:數(shù)字電位計 IC Sngl 7B V I2C POT RoHS:否 制造商:Maxim Integrated 電阻:200 Ohms 溫度系數(shù):35 PPM / C 容差:25 % POT 數(shù)量:Dual 每 POT 分接頭:256 弧刷存儲器:Volatile 緩沖刷: 數(shù)字接口:Serial (3-Wire, SPI) 描述/功能:Dual Volatile Low Voltage Linear Taper Digital Potentiometer 工作電源電壓:1.7 V to 5.5 V 電源電流:27 uA 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TQFN-16 封裝:Reel
MCP4531-104E/MS 制造商:Microchip Technology Inc 功能描述:; LEADED PROCESS COMPATIBLE:YES; PEAK RE
MCP4531-502E/MS 功能描述:數(shù)字電位計 IC Sngl 7B V I2C POT RoHS:否 制造商:Maxim Integrated 電阻:200 Ohms 溫度系數(shù):35 PPM / C 容差:25 % POT 數(shù)量:Dual 每 POT 分接頭:256 弧刷存儲器:Volatile 緩沖刷: 數(shù)字接口:Serial (3-Wire, SPI) 描述/功能:Dual Volatile Low Voltage Linear Taper Digital Potentiometer 工作電源電壓:1.7 V to 5.5 V 電源電流:27 uA 最大工作溫度:+ 125 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:TQFN-16 封裝:Reel
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。

采購需求

(若只采購一條型號，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進(jìn)入我的后臺，查看報價

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進(jìn)入我的后臺，查看報價

*型號 *數(shù)量 廠商 批號 封裝
添加更多采購

我的聯(lián)系方式

*
*
*