- 您现在的位置：买卖IC网 > PDF目录16414 > DP83848C-MAU-EK (National Semiconductor)BOARD EVALUATION DP83848C PDF资料下载
参数资料
| 型号： | DP83848C-MAU-EK |
| 厂商： | National Semiconductor |
| 文件页数： | 10/86页 |
| 文件大小： | 0K |
| 描述： | BOARD EVALUATION DP83848C |
| 标准包装： | 1 |
| 主要目的： | 接口，以太网 |
| 已用 IC / 零件： | DP83848C |
| 已供物品： | 板 |
| 相关产品： | DP83848CVVX/NOPBTR-ND - TXRX ETHERNET PHYTER 48-LQFP DP83848CVV-ND - IC TXRX ETHERNET PHYTER 48-LQFP |
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页当前第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
17
www.national.com
DP
83
84
8
C
ANAR. Updating the ANAR to suppress an ability is one
way for a management agent to change (restrict) the tech-
nology that is used.
The Auto-Negotiation Link Partner Ability Register
(ANLPAR) at address 05h is used to receive the base link
code word as well as all next page code words during the
negotiation. Furthermore, the ANLPAR will be updated to
either 0081h or 0021h for parallel detection to either 100
Mb/s or 10 Mb/s respectively.
The Auto-Negotiation Expansion Register (ANER) indi-
cates additional Auto-Negotiation status. The ANER pro-
vides status on:
— Whether or not a Parallel Detect Fault has occurred
— Whether or not the Link Partner supports the Next Page
function
— Whether or not the DP83848C supports the Next Page
function
— Whether or not the current page being exchanged by
Auto-Negotiation has been received
— Whether or not the Link Partner supports Auto-Negotia-
tion
2.1.3 Auto-Negotiation Parallel Detection
The DP83848C supports the Parallel Detection function as
defined in the IEEE 802.3u specification. Parallel Detection
requires both the 10 Mb/s and 100 Mb/s receivers to moni-
tor the receive signal and report link status to the Auto-
Negotiation function. Auto-Negotiation uses this informa-
tion to configure the correct technology in the event that the
Link Partner does not support Auto-Negotiation but is
transmitting link signals that the 100BASE-TX or 10BASE-
T PMAs recognize as valid link signals.
If the DP83848C completes Auto-Negotiation as a result of
Parallel Detection, bits 5 and 7 within the ANLPAR register
will be set to reflect the mode of operation present in the
Link Partner. Note that bits 4:0 of the ANLPAR will also be
set to 00001 based on a successful parallel detection to
indicate a valid 802.3 selector field. Software may deter-
mine that negotiation completed via Parallel Detection by
reading a zero in the Link Partner Auto-Negotiation Able bit
once the Auto-Negotiation Complete bit is set. If configured
for parallel detect mode and any condition other than a sin-
gle good link occurs then the parallel detect fault bit will be
set.
2.1.4 Auto-Negotiation Restart
Once Auto-Negotiation has completed, it may be restarted
at any time by setting bit 9 (Restart Auto-Negotiation) of the
BMCR to one. If the mode configured by a successful Auto-
Negotiation loses a valid link, then the Auto-Negotiation
process will resume and attempt to determine the configu-
ration for the link. This function ensures that a valid config-
uration is maintained if the cable becomes disconnected.
A renegotiation request from any entity, such as a manage-
ment agent, will cause the DP83848C to halt any transmit
data and link pulse activity until the break_link_timer
expires (~1500 ms). Consequently, the Link Partner will go
into link fail and normal Auto-Negotiation resumes. The
DP83848C
will
resume Auto-Negotiation after
the
break_link_timer has expired by issuing FLP (Fast Link
Pulse) bursts.
2.1.5 Enabling Auto-Negotiation via Software
It is important to note that if the DP83848C has been initial-
ized upon power-up as a non-auto-negotiating device
(forced technology), and it is then required that Auto-Nego-
tiation or re-Auto-Negotiation be initiated via software,
bit 12 (Auto-Negotiation Enable) of the Basic Mode Control
Register (BMCR) must first be cleared and then set for any
Auto-Negotiation function to take effect.
2.1.6 Auto-Negotiation Complete Time
Parallel detection and Auto-Negotiation take approximately
2-3 seconds to complete. In addition, Auto-Negotiation with
next page should take approximately 2-3 seconds to com-
plete, depending on the number of next pages sent.
Refer to Clause 28 of the IEEE 802.3u standard for a full
description of the individual timers related to Auto-Negotia-
tion.
2.2 Auto-MDIX
When enabled, this function utilizes Auto-Negotiation to
determine the proper configuration for transmission and
reception of data and subsequently selects the appropriate
MDI pair for MDI/MDIX operation. The function uses a ran-
dom seed to control switching of the crossover circuitry.
This implementation complies with the corresponding IEEE
802.3 Auto-Negotiation and Crossover Specifications.
Auto-MDIX is enabled by default and can be configured via
strap or via PHYCR (0x19h) register, bits [15:14].
Neither Auto-Negotiation nor Auto-MDIX is required to be
enabled in forcing crossover of the MDI pairs. Forced
crossover can be achieved through the FORCE_MDIX bit,
bit 14 of PHYCR (0x19h) register.
Note: Auto-MDIX will not work in a forced mode of opera-
tion.
相关PDF资料 |
PDF描述 |
|---|---|
| 2-5492591-0 | CA 50/125UMRIS SCDUP/2.5BAY 20M1 |
| 6278899-1 | CA,62.5,MTRJ-SC |
| L-07W18NKV4T | WIREWOUND INDUCTOR 18NH 0402 |
| ECM24DRSN | CONN EDGECARD 48POS DIP .156 SLD |
| 1-6828318-2 | C/A,2.0MM,RISER,XG,AQUA,LC-SC |
相关代理商/技术参数 |
参数描述 |
|---|---|
| DP83848C-POE-EK | 功能描述:以太网开发工具 DP83848 POE CARD COMM TEMP RoHS:否 制造商:Micrel 产品:Evaluation Boards 类型:Ethernet Transceivers 工具用于评估:KSZ8873RLL 接口类型:RMII 工作电源电压: |
| DP83848CVV | 制造商:Texas Instruments 功能描述:IC, 10/100 ETHERNET PHY, SMD, LQFP48 |
| DP83848CVV/NOPB | 功能描述:以太网 IC PHYTER COMMERCIAL TEMP SGL PORT RoHS:否 制造商:Micrel 产品:Ethernet Switches 收发器数量:2 数据速率:10 Mb/s, 100 Mb/s 电源电压-最大:1.25 V, 3.45 V 电源电压-最小:1.15 V, 3.15 V 最大工作温度:+ 85 C 封装 / 箱体:QFN-64 封装:Tray |
| DP83848CVV/NOPB | 制造商:Texas Instruments 功能描述:Ethernet Transceiver |
| DP83848CVVX | 制造商:Texas Instruments 功能描述:PHY 1-CH 10Mbps/100Mbps 48-Pin LQFP T/R |
发布紧急采购，3分钟左右您将得到回复。