參數(shù)資料
型號(hào)： KSZ8895MQI
廠商： Micrel Inc
文件頁(yè)數(shù)： 7/119頁(yè)
文件大?。?/td> 0K
描述： IC ETHERNET SWITCH 5PORT 128PQFP
特色產(chǎn)品： KSZ8895MQ Ethernet Switches
標(biāo)準(zhǔn)包裝： 66
系列： *
其它名稱： 576-3997
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)當(dāng)前第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)第20頁(yè)第21頁(yè)第22頁(yè)第23頁(yè)第24頁(yè)第25頁(yè)第26頁(yè)第27頁(yè)第28頁(yè)第29頁(yè)第30頁(yè)第31頁(yè)第32頁(yè)第33頁(yè)第34頁(yè)第35頁(yè)第36頁(yè)第37頁(yè)第38頁(yè)第39頁(yè)第40頁(yè)第41頁(yè)第42頁(yè)第43頁(yè)第44頁(yè)第45頁(yè)第46頁(yè)第47頁(yè)第48頁(yè)第49頁(yè)第50頁(yè)第51頁(yè)第52頁(yè)第53頁(yè)第54頁(yè)第55頁(yè)第56頁(yè)第57頁(yè)第58頁(yè)第59頁(yè)第60頁(yè)第61頁(yè)第62頁(yè)第63頁(yè)第64頁(yè)第65頁(yè)第66頁(yè)第67頁(yè)第68頁(yè)第69頁(yè)第70頁(yè)第71頁(yè)第72頁(yè)第73頁(yè)第74頁(yè)第75頁(yè)第76頁(yè)第77頁(yè)第78頁(yè)第79頁(yè)第80頁(yè)第81頁(yè)第82頁(yè)第83頁(yè)第84頁(yè)第85頁(yè)第86頁(yè)第87頁(yè)第88頁(yè)第89頁(yè)第90頁(yè)第91頁(yè)第92頁(yè)第93頁(yè)第94頁(yè)第95頁(yè)第96頁(yè)第97頁(yè)第98頁(yè)第99頁(yè)第100頁(yè)第101頁(yè)第102頁(yè)第103頁(yè)第104頁(yè)第105頁(yè)第106頁(yè)第107頁(yè)第108頁(yè)第109頁(yè)第110頁(yè)第111頁(yè)第112頁(yè)第113頁(yè)第114頁(yè)第115頁(yè)第116頁(yè)第117頁(yè)第118頁(yè)第119頁(yè)
PIC16(L)F1782/3
DS41579C-page 104
Preliminary
2011-2012 Microchip Technology Inc.
12.2
Using the Data EEPROM
The data EEPROM is a high-endurance, byte address-
able array that has been optimized for the storage of
frequently changing information (e.g., program vari-
ables or other data that are updated often). When vari-
ables in one section change frequently, while variables
in another section do not change, it is possible to
exceed the total number of write cycles to the
EEPROM without exceeding the total number of write
cycles to a single byte. Refer to Section 30.0 “Electri-
cal Specifications”. If this is the case, then a refresh
of the array must be performed. For this reason, vari-
ables that change infrequently (such as constants, IDs,
calibration, etc.) should be stored in Flash program
memory.
12.2.1
READING THE DATA EEPROM
MEMORY
To read a data memory location, the user must write the
address to the EEADRL register, clear the EEPGD and
CFGS control bits of the EECON1 register, and then
set control bit RD. The data is available at the very next
cycle, in the EEDATL register; therefore, it can be read
in the next instruction. EEDATL will hold this value until
another read or until it is written to by the user (during
a write operation).
EXAMPLE 12-1:
DATA EEPROM READ
12.2.2
WRITING TO THE DATA EEPROM
MEMORY
To write an EEPROM data location, the user must first
write the address to the EEADRL register and the data
to the EEDATL register. Then the user must follow a
specific sequence to initiate the write for each byte.
The write will not initiate if the above sequence is not
followed exactly (write 55h to EECON2, write AAh to
EECON2, then set the WR bit) for each byte. Interrupts
should be disabled during this code segment.
Additionally, the WREN bit in EECON1 must be set to
enable write. This mechanism prevents accidental
writes to data EEPROM due to errant (unexpected)
code execution (i.e., lost programs). The user should
keep the WREN bit clear at all times, except when
updating EEPROM. The WREN bit is not cleared
by hardware.
After a write sequence has been initiated, clearing the
WREN bit will not affect this write cycle. The WR bit will
be inhibited from being set unless the WREN bit is set.
At the completion of the write cycle, the WR bit is
cleared in hardware and the EE Write Complete
Interrupt Flag bit (EEIF) is set. The user can either
enable this interrupt or poll this bit. EEIF must be
cleared by software.
12.2.3
PROTECTION AGAINST SPURIOUS
WRITE
There are conditions when the user may not want to
write to the data EEPROM memory. To protect against
spurious EEPROM writes, various mechanisms have
been built-in. On power-up, WREN is cleared. Also, the
Power-up Timer (64 ms duration) prevents EEPROM
write.
The write initiate sequence and the WREN bit together
help prevent an accidental write during:
Brown-out
Power Glitch
Software Malfunction
12.2.4
DATA EEPROM OPERATION
DURING CODE-PROTECT
Data memory can be code-protected by programming
the CPD bit in the Configuration Words to ‘0’.
When the data memory is code-protected, only the
CPU is able to read and write data to the data
EEPROM. It is recommended to code-protect the pro-
gram memory when code-protecting data memory.
This prevents anyone from replacing your program with
a program that will access the contents of the data
EEPROM.
Note:
Data EEPROM can be read regardless of
the setting of the CPD bit.
BANKSEL EEADRL
;
MOVLW
DATA_EE_ADDR ;
MOVWF
EEADRL
;Data Memory
;Address to read
BCF
EECON1, CFGS ;Deselect Config space
BCF
EECON1, EEPGD;Point to DATA memory
BSF
EECON1, RD
;EE Read
MOVF
EEDATL, W
;W = EEDATL
相關(guān)PDF資料
PDF描述
KSZ8895MQ IC ETHERNET SW 5PORT 128-PQFP
KSZ8993FL IC CONV MED 10/100 SGL 128PQFP
KSZ8993MLI IC SWITCH 10/100 3PORT 128-PQFP
KSZ8993ML IC SWITCH 10/100 W/TXRX 128PQFP
KSZ8995FQ IC SWITCH 10/100 5PORT 128-PQFP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
KSZ8895MQXCA 功能描述:Ethernet Switch 10/100 Base-T/TX I2C, SPI Interface 128-PQFP (14x20) 制造商:microchip technology 系列:- 包裝:托盤 零件狀態(tài):有效 協(xié)議:以太網(wǎng) 功能:開關(guān) 接口:I2C，SPI 標(biāo)準(zhǔn):10/100 Base-T/TX 電壓 - 電源:1.8V，2.5V，3.3V 電流 - 電源:129mA 工作溫度:0°C ~ 70°C 封裝/外殼:128-BFQFP 供應(yīng)商器件封裝:128-PQFP（14x20） 標(biāo)準(zhǔn)包裝:66
KSZ8895MQXIA 功能描述:Ethernet Switch 10/100 Base-T/TX I2C, SPI Interface 128-PQFP (14x20) 制造商:microchip technology 系列:- 包裝:托盤 零件狀態(tài):有效 協(xié)議:以太網(wǎng) 功能:開關(guān) 接口:I2C，SPI 標(biāo)準(zhǔn):10/100 Base-T/TX 電壓 - 電源:1.8V，2.5V，3.3V 電流 - 電源:129mA 工作溫度:-40°C ~ 85°C 封裝/外殼:128-BFQFP 供應(yīng)商器件封裝:128-PQFP（14x20） 標(biāo)準(zhǔn)包裝:66
KSZ8895RQ 功能描述:以太網(wǎng) IC 5-port Switch, one SW5-RMII and one P5-RMII Interface RoHS:否 制造商:Micrel 產(chǎn)品:Ethernet Switches 收發(fā)器數(shù)量:2 數(shù)據(jù)速率:10 Mb/s, 100 Mb/s 電源電壓-最大:1.25 V, 3.45 V 電源電壓-最小:1.15 V, 3.15 V 最大工作溫度:+ 85 C 封裝 / 箱體:QFN-64 封裝:Tray
KSZ8895RQ TR 功能描述:以太網(wǎng) IC 5-port Switch, one SW5-RMII and one P5-RMII Interface RoHS:否 制造商:Micrel 產(chǎn)品:Ethernet Switches 收發(fā)器數(shù)量:2 數(shù)據(jù)速率:10 Mb/s, 100 Mb/s 電源電壓-最大:1.25 V, 3.45 V 電源電壓-最小:1.15 V, 3.15 V 最大工作溫度:+ 85 C 封裝 / 箱體:QFN-64 封裝:Tray
KSZ8895RQ-EVAL 功能描述:以太網(wǎng)開發(fā)工具 5-port Switch, one SW5-RMII and one P5-RMII Interface - Evaluation Board RoHS:否 制造商:Micrel 產(chǎn)品:Evaluation Boards 類型:Ethernet Transceivers 工具用于評(píng)估:KSZ8873RLL 接口類型:RMII 工作電源電壓:
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

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

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

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*