参数资料
型号: TOOLSTICK530ADC
厂商: Silicon Laboratories Inc
文件页数: 45/220页
文件大小: 0K
描述: DAUGHTR CARD TOOLSTICK C8051F530
标准包装: 1
系列: ToolStick
类型: MCU
适用于相关产品: C8051F530A
所含物品:
产品目录页面: 626 (CN2011-ZH PDF)
配用: 336-1345-ND - TOOLSTICK BASE ADAPTER
336-1182-ND - ADAPTER USB DEBUG FOR C8051FXXX
相关产品: 336-1486-5-ND - IC 8051 MCU 8K FLASH 20TSSOP
336-1485-5-ND - IC 8051 MCU 8K FLASH 20QFN
其它名称: 336-1487
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页当前第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页第94页第95页第96页第97页第98页第99页第100页第101页第102页第103页第104页第105页第106页第107页第108页第109页第110页第111页第112页第113页第114页第115页第116页第117页第118页第119页第120页第121页第122页第123页第124页第125页第126页第127页第128页第129页第130页第131页第132页第133页第134页第135页第136页第137页第138页第139页第140页第141页第142页第143页第144页第145页第146页第147页第148页第149页第150页第151页第152页第153页第154页第155页第156页第157页第158页第159页第160页第161页第162页第163页第164页第165页第166页第167页第168页第169页第170页第171页第172页第173页第174页第175页第176页第177页第178页第179页第180页第181页第182页第183页第184页第185页第186页第187页第188页第189页第190页第191页第192页第193页第194页第195页第196页第197页第198页第199页第200页第201页第202页第203页第204页第205页第206页第207页第208页第209页第210页第211页第212页第213页第214页第215页第216页第217页第218页第219页第220页
Rev. 1.4
139
C8051F52x/F53x
14.2. External Oscillator Drive Circuit
The external oscillator circuit may drive an external crystal, ceramic resonator, capacitor, or RC network. A
CMOS clock may also provide a clock input. For a crystal or ceramic resonator configuration, the crys-
tal/resonator must be wired across the XTAL1 and XTAL2 pins as shown in Option 1 of Figure 14.1. A
10 M
resistor also must be wired across the XTAL1 and XTAL2 pins for the crystal/resonator configura-
tion. In RC, capacitor, or CMOS clock configuration, the clock source should be wired to the XTAL2 pin as
shown in Option 2, 3, or 4 of Figure 14.1. The type of external oscillator must be selected in the OSCXCN
register,
and
the
frequency
control
bits
(XFCN)
must
be
selected
appropriately
(see
Important Note on External Oscillator Usage: Port pins must be configured when using the external
oscillator circuit. When the external oscillator drive circuit is enabled in crystal/resonator mode, Port pins
P0.7 and P1.0 ('F53x/'F53xA) or P0.2 and P0.3 ('F52x/'F52xA) are used as XTAL1 and XTAL2 respec-
tively. When the external oscillator drive circuit is enabled in capacitor, RC, or CMOS clock mode, Port pin
P1.0 ('F53x/'F53xA) or P0.3 ('F52x/'F52xA) is used as XTAL2. The Port I/O Crossbar should be configured
to skip the Port pins used by the oscillator circuit; see Section “13.1. Priority Crossbar Decoder” on
page 122 for Crossbar configuration. Additionally, when using the external oscillator circuit in crystal/reso-
nator, capacitor, or RC mode, the associated Port pins should be configured as analog inputs. In CMOS
clock mode, the associated pin should be configured as a digital input. See Section “13.2. Port I/O Initial-
ization” on page 126 for details on Port input mode selection.
14.2.1. Clocking Timers Directly Through the External Oscillator
The external oscillator source divided by eight is a clock option for the timers (Section “18. Timers” on
page 182) and the Programmable Counter Array (PCA) (Section “19. Programmable Counter Array
(PCA0)” on page 195). When the external oscillator is used to clock these peripherals, but is not used as
the system clock, the external oscillator frequency must be less than or equal to the system clock fre-
quency. In this configuration, the clock supplied to the peripheral (external oscillator / 8) is synchronized
with the system clock; the jitter associated with this synchronization is limited to ±0.5 system clock cycles.
14.2.2. External Crystal Example
If a crystal or ceramic resonator is used as an external oscillator source for the MCU, the circuit should be
configured as shown in Figure 14.1, Option 1. The External Oscillator Frequency Control value (XFCN)
should be chosen from the Crystal column of the table in SFR Definition 14.4. For example, a 12 MHz crys-
tal requires an XFCN setting of 111b.
When the crystal oscillator is first enabled, the oscillator amplitude detection circuit requires a settling time
to achieve proper bias. Introducing a delay of 1 ms between enabling the oscillator and checking the
XTLVLD bit will prevent a premature switch to the external oscillator as the system clock. Switching to the
external oscillator before the crystal oscillator has stabilized can result in unpredictable behavior. The rec-
ommended procedure is:
1. Configure XTAL1 and XTAL2 pins by writing 1 to the port latch.
2. Configure XTAL1 and XTAL2 as analog inputs.
3. Enable the external oscillator.
4. Wait at least 1 ms.
5. Poll for XTLVLD => 1.
6. Switch the system clock to the external oscillator.
Note:
Tuning-fork crystals may require additional settling time before XTLVLD returns a valid result.
The capacitors shown in the external crystal configuration provide the load capacitance required by the
crystal for correct oscillation. These capacitors are "in series" as seen by the crystal and "in parallel" with
the stray capacitance of the XTAL1 and XTAL2 pins.
相关PDF资料
PDF描述
1546452-2 CABLE PLUG-PLUG ETHERNET 5METER
XC8102AA01MR-G IC LOAD SWITCH 400MA SOT-25
1546452-1 CABLE PLUG-PLUG ETHERNET 2METER
RSM08DRKI CONN EDGECARD 16POS DIP .156 SLD
AP2411FGE-7 IC USB SWITCH DFN3030-8
相关代理商/技术参数
参数描述
TOOLSTICK530MPP 功能描述:插座和适配器 C8051F530/1/3/4/6/7- IM MCUs Dev Tool RoHS:否 制造商:Silicon Labs 产品:Adapter 用于:EM35x
TOOLSTICK530TPP 功能描述:插座和适配器 C8051F530/1/3/4/6/7- IT MCUs Dev Tool RoHS:否 制造商:Silicon Labs 产品:Adapter 用于:EM35x
ToolStick540DC 功能描述:子卡和OEM板 ToolStick C8051F540 Daughter Card RoHS:否 制造商:BeagleBoard by CircuitCo 产品:BeagleBone LCD4 Boards 用于:BeagleBone - BB-Bone - Open Source Development Kit
ToolStick542PP 功能描述:插座和适配器 ToolStick Prog. Platform RoHS:否 制造商:Silicon Labs 产品:Adapter 用于:EM35x
ToolStick560DC 功能描述:子卡和OEM板 ToolStick C8051F560 Daughter Card RoHS:否 制造商:BeagleBoard by CircuitCo 产品:BeagleBone LCD4 Boards 用于:BeagleBone - BB-Bone - Open Source Development Kit