參數(shù)資料
型號: LM32
廠商: National Semiconductor Corporation
元件分類: 溫度/濕度傳感器
英文描述: Dual Thermal Diode Temperature Sensor with SensorPath Bus
中文描述: 雙熱二極管溫度傳感器SensorPath總線
文件頁數(shù): 11/24頁
文件大?。?/td> 340K
代理商: LM32
1.0 Functional Description
(Continued)
1.3.2 Read Transaction
During a read transaction, the master reads data from a
register at a specified address within a slave. A read trans-
action begins with a Start Bit and ends with an ACK bit, as
shown in
Figure 5
.
Device Number
This is the address of the LM32 device
accessed. Address "000" is a broadcast address and can
be responded to by all the slave devices. The LM32
ignores the broadcast address during a read transaction.
Internal Address
The address of a register within the
LM32 that is read.
Read/Write (R/W)
A "1" indicates a read transaction.
Data Bits
During a read transaction the data bits are
driven by the LM32. Data is transferred serially with the
most significant bit first. This allows throughput optimiza-
tion based on the information that needs to be read.
The LM32 supports 8-bit or 16-bit data fields, as de-
scribed in
Section 2.0
"Register Set".
Even Parity (EP)
This bit is based on all preceding bits
(device number, internal address, Read/Write and data
bits) and the parity bit itself. The parity -number of 1’s - of
all the preceding bits and the parity bit must be even - i.e.,
the result must be 0. During a read transaction, the EP bit
is sent by the LM32 to the master to allow the master to
check the received data before using it.
Acknowledge (ACK)
During a read transaction theACK
bit is sent by the master indicating that the EP bit was
received and was found to be correct, when compared to
the data preceding it, and that no conflict was detected
on the bus (excluding Attention Request - see
Section
1.3.5
"Attention Request Transaction"). A read transfer is
considered "complete" only when theACK bit is received.
A transaction that was not positively acknowledged is not
considered "complete" by the LM32 and following are
performed:
— The BER bit in the LM32 Device Status register is set
— The LM32 generates an Attention Request before, or
together with the Start Bit of the next transaction
A transaction that was not positively acknowledged is
also not considered "complete" by the master (i.e. inter-
nal operations related to the transaction are not per-
formed). The transaction may be repeated by the master,
after detecting the source of the Attention Request (the
LM32 that has a set BER bit in the Device Status regis-
ter). Note that the SensorPath protocol neither forces, nor
automates re-execution of the transaction by the master.
The values of the ACK bit are:
— 1: Data was received correctly
— 0: An error was detected (no-acknowledge).
1.3.3 Write Transaction
In a write transaction, the master writes data to a register at
a specified address in the LM32. A write transaction begins
with a Start Bit and ends with an ACK Data Bit, as show in
Figure 6
.
Device Number
This is the address of the slave device
accessed. Address "000" is a broadcast address and is
responded to by all the slave devices. The LM32 re-
sponds to broadcast messages to the Device Control
Register.
Internal Address
This is the register address in the
LM32 that will be written.
Read/Write (R/W)
A "0" data bit directs a write transac-
tion.
20071108
FIGURE 4. Bus Reset Transaction
20071109
FIGURE 5. Read Transaction, master reads data from LM32
L
www.national.com
11
相關(guān)PDF資料
PDF描述
LM3302J QUADRUPLE DIFFERENTIAL COMPARATOR
LM3302M96 Quad Voltage Comparators for Industrial, Commercial and Military Applications
LM3302N Quad Voltage Comparators for Industrial, Commercial and Military Applications
LM3302 Quad Voltage Comparators for Industrial, Commercial and Military Applications
LM3311 Step-Up PWM DC/DC Converter with Integrated LDO, Op-Amp, and Gate Pulse Modulation Switch
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LM320 制造商:NSC 制造商全稱:National Semiconductor 功能描述:Series 3-Terminal Negative Regulators
LM3200 制造商:WABER 功能描述:
LM3200_05 制造商:NSC 制造商全稱:National Semiconductor 功能描述:Miniature, Adjustable, Step-Down DC-DC Converter with Bypass Mode for RF Power Amplifiers
LM320081 制造商:Sharp Microelectronics 功能描述:4.7 DFSTN REFLECTIVE 3
LM3200TL 制造商:Rochester Electronics LLC 功能描述: 制造商:Texas Instruments 功能描述:IC BUCK CONVERTER POWERWISE 3200