參數資料
型號: SC1100UFH-266
廠商: National Semiconductor Corporation
英文描述: Geode⑩ Information Appliance On a Chip
中文描述: Geode⑩信息家電在一個芯片
文件頁數: 99/348頁
文件大?。?/td> 2063K
代理商: SC1100UFH-266
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁第65頁第66頁第67頁第68頁第69頁第70頁第71頁第72頁第73頁第74頁第75頁第76頁第77頁第78頁第79頁第80頁第81頁第82頁第83頁第84頁第85頁第86頁第87頁第88頁第89頁第90頁第91頁第92頁第93頁第94頁第95頁第96頁第97頁第98頁當前第99頁第100頁第101頁第102頁第103頁第104頁第105頁第106頁第107頁第108頁第109頁第110頁第111頁第112頁第113頁第114頁第115頁第116頁第117頁第118頁第119頁第120頁第121頁第122頁第123頁第124頁第125頁第126頁第127頁第128頁第129頁第130頁第131頁第132頁第133頁第134頁第135頁第136頁第137頁第138頁第139頁第140頁第141頁第142頁第143頁第144頁第145頁第146頁第147頁第148頁第149頁第150頁第151頁第152頁第153頁第154頁第155頁第156頁第157頁第158頁第159頁第160頁第161頁第162頁第163頁第164頁第165頁第166頁第167頁第168頁第169頁第170頁第171頁第172頁第173頁第174頁第175頁第176頁第177頁第178頁第179頁第180頁第181頁第182頁第183頁第184頁第185頁第186頁第187頁第188頁第189頁第190頁第191頁第192頁第193頁第194頁第195頁第196頁第197頁第198頁第199頁第200頁第201頁第202頁第203頁第204頁第205頁第206頁第207頁第208頁第209頁第210頁第211頁第212頁第213頁第214頁第215頁第216頁第217頁第218頁第219頁第220頁第221頁第222頁第223頁第224頁第225頁第226頁第227頁第228頁第229頁第230頁第231頁第232頁第233頁第234頁第235頁第236頁第237頁第238頁第239頁第240頁第241頁第242頁第243頁第244頁第245頁第246頁第247頁第248頁第249頁第250頁第251頁第252頁第253頁第254頁第255頁第256頁第257頁第258頁第259頁第260頁第261頁第262頁第263頁第264頁第265頁第266頁第267頁第268頁第269頁第270頁第271頁第272頁第273頁第274頁第275頁第276頁第277頁第278頁第279頁第280頁第281頁第282頁第283頁第284頁第285頁第286頁第287頁第288頁第289頁第290頁第291頁第292頁第293頁第294頁第295頁第296頁第297頁第298頁第299頁第300頁第301頁第302頁第303頁第304頁第305頁第306頁第307頁第308頁第309頁第310頁第311頁第312頁第313頁第314頁第315頁第316頁第317頁第318頁第319頁第320頁第321頁第322頁第323頁第324頁第325頁第326頁第327頁第328頁第329頁第330頁第331頁第332頁第333頁第334頁第335頁第336頁第337頁第338頁第339頁第340頁第341頁第342頁第343頁第344頁第345頁第346頁第347頁第348頁
Revision 1.1
99
www.national.com
G
SuperI/O Module
(Continued)
4.7.4
According to this rule, the master generates an acknowl-
edge clock pulse after each byte transfer, and the receiver
sends an acknowledge signal after every byte received.
There are two exceptions to this rule:
Acknowledge After Every Byte Rule
When the master is the receiver, it must indicate to the
transmitter the end of data by not acknowledging (nega-
tive acknowledge) the last byte clocked out of the slave.
This negative acknowledge still includes the acknowl-
edge clock pulse (generated by the master), but the
ABD line is not pulled down.
When the receiver is full, otherwise occupied, or a
problem has occurred, it sends a negative acknowledge
to indicate that it cannot accept additional data bytes.
4.7.5
Each device on the bus has a unique address. Before any
data is transmitted, the master transmits the address of the
slave being addressed. The slave device should send an
acknowledge signal on the ABD line, once it recognizes its
address.
Addressing Transfer Formats
The address consists of the first 7 bits after a Start Condi-
tion. The direction of the data transfer (R/W#) depends on
the bit sent after the address, the eighth bit. A low-to-high
transition during a ABC high period indicates the Stop Con-
dition, and ends the transaction of ABD (see Figure 4-17).
When the address is sent, each device in the system com-
pares this address with its own. If there is a match, the
device considers itself addressed and sends an acknowl-
edge signal. Depending on the state of the R/W# bit (1 =
Read, 0 = Write), the device acts either as a transmitter or
a receiver.
The I
2
C bus protocol allows a general call address to be
sent to all slaves connected to the bus. The first byte sent
specifies the general call address (00h) and the second
byte specifies the meaning of the general call (for example,
write slave address by software only). Those slaves that
require data acknowledge the call, and become slave
receivers; other slaves ignore the call.
4.7.6
Multiple master devices on the bus require arbitration
between their conflicting bus access demands. Control of
the bus is initially determined according to address bits and
clock cycle. If the masters are trying to address the same
slave, data comparisons determine the outcome of this
arbitration. In master mode, the device immediately aborts
a transaction if the value sampled on the ABD line differs
from the value driven by the device. (An exception to this
rule is ABD while receiving data. The lines may be driven
low by the slave without causing an abort.)
Arbitration on the Bus
The ABC signal is monitored for clock synchronization and
to allow the slave to stall the bus. The actual clock period is
set by the master with the longest clock period, or by the
slave stall period. The clock high period is determined by
the master with the shortest clock high period.
When an abort occurs during the address transmission, a
master that identifies the conflict should give up the bus,
switch to slave mode and continue to sample ABD to check
if it is being addressed by the winning master on the bus.
4.7.7
Master Mode
Requesting Bus Mastership
An ACCESS.bus transaction starts with a master device
requesting bus mastership. It asserts a Start Condition, fol-
lowed by the address of the device it wants to access. If
this transaction is successfully completed, the software
may assume that the device has become the bus master.
For the device to become the bus master, the software
should perform the following steps:
1)
Configure ACBCTL1[2] to the desired operation mode.
(Polling or Interrupt) and set the ACBCTL1[0]. This
causes the ACB to issue a Start Condition on the
ACCESS.bus when the ACCESS.bus becomes free
(ACBCST[1] is cleared, or other conditions that can
delay start). It then stalls the bus by holding ABC low.
2)
If a bus conflict is detected (i.e., another device pulls
down the ABC signal), the ACBST[5] is set.
3)
If there is no bus conflict, ACBST[1] and ACBST[6] are
set.
4)
If the ACBCTL1[2] is set and either ACBST[5] or
ACBST[6] is set, an interrupt is issued.
Figure 4-17. A Complete ACCESS.bus Data Transaction
S
P
Start
Condition
Stop
Condition
ABD
ABC
1 - 7
8
9
1 - 7
8
9
1 - 7
8
9
Address R/W# ACK
Data
ACK
Data
ACK
相關PDF資料
PDF描述
SC1100UFH-300 Geode⑩ Information Appliance On a Chip
SC11372 MOBILE RADIO ANALOG PROCESSOR
SC11372CQ MOBILE RADIO ANALOG PROCESSOR
SC140 High-Performance Fix-Point DSP Core(高性能定點型數字信號處理器內核)
SC14402RVJG Complete Baseband Processor for DECT Handsets
相關代理商/技術參數
參數描述
SC1100UFH-266 B1 制造商:Advanced Micro Devices 功能描述:I3O IC OPN
SC1100UFH-300 制造商:NSC 制造商全稱:National Semiconductor 功能描述:Geode⑩ Information Appliance On a Chip
SC1101 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:VOLTAGE MODE PWM CONTROLLER
SC1101_05 制造商:SEMTECH 制造商全稱:Semtech Corporation 功能描述:Asynchronous Voltage Mode PWM Controller
SC11014 制造商:未知廠家 制造商全稱:未知廠家 功能描述:300 / 1200 Bit Per Second Modem