參數(shù)資料
型號: AM79C976
廠商: Advanced Micro Devices, Inc.
英文描述: PCnet-PRO⑩ 10/100 Mbps PCI Ethernet Controller
中文描述: PCnet -專業(yè)⑩個10/100Mbps PCI以太網(wǎng)控制器
文件頁數(shù): 131/309頁
文件大小: 2070K
代理商: AM79C976
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頁當(dāng)前第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
8/01/00
Am79C976
131
P R E L I M I N A R Y
#*!!
Offset 050h
CMD2 is a command-style register. All bits in this reg-
ister are cleared to 0 when the RST pin is asserted, be-
fore the serial EEPROM is read, and after a serial
EEPROM read error.
Table 43.
CMD2: Command2 Register
3
RX_SPND
Receive Suspend. Setting this bit causes the receiver to suspend its activities without stopping in
the middle of a frame reception. After the receiver suspends its activities, the DMA controller
continues copying data from the Receive FIFO into host system memory until the FIFO is empty
or until no more receive descriptors are available.
After the Receive FIFO has been emptied or after all receive descriptors have been used, the
receive DMA controller suspends its polling activity, and the RX_SUSPENDED bit in the Status
register and the Suspend Interrupt (SPNDINT) bit in the Interrupt register will be set. Setting the
SPNDINT bit will cause an interrupt to occur if interrupts are enabled and the SPNDINTEN bit in
the Interrupt Enable register is set.
2
TX_SPND
Transmit Suspend. Setting this bit causes the transmitter to suspend its activities without stopping
in the middle of a frame transmission. After the transmitter suspends its activities, the DMA
controller continues copying data from host system memory into the Transmit FIFO until the FIFO
is full or until no more transmit descriptors are available.
After the Transmit FIFO has been filled or after all transmit descriptors have been used, the
transmit DMA controller suspends its polling activity, and the TX_SUSPENDED bit in the Status
register and the Suspend Interrupt (SPNDINT) bit in the Interrupt register will be set. Setting the
SPNDINT bit will cause an interrupt to occur if interrupts are enabled and the SPNDINTEN bit in
the Interrupt Enable register is set.
1
INTREN
Interrupt Enable. This bit allows INTA to be asserted if any bit in the Interrupt register is set. If
INTREN is cleared to 0, INTA will not be asserted, regardless of the state of the Interrupt register.
INTREN is not an alias of the IENA bit in CSR0.
0
RUN
Setting the RUN bit enables the Am79C976 controller to start processing descriptors and
transmitting and receiving packets.
Clearing the RUN bit to 0 abruptly disables the transmitter, receiver, and descriptor processing
logic, possibly while a frame is being transmitted or received.
The act of changing the RUN bit from 1 to 0 causes the following bits to be reset to 0: IENA,
TX_SPND, RX_SPND, TDMD, RDMD, UINTCMD, TX_FAST_SPND, RINT, TINT, TXSTRTINT,
TXDNINT, MPINT, and UINT.
Bit
Name
Description
Bit
Name
Description
31
VAL3
Value bit for byte 3. The value of this bit is written to any bits in the CMD2 register that correspond
to bits in the CMD2[30:24] bit map field that are set to 1.
30
NOUFLO
No Underflow on Transmit. When the NOUFLO bit is set to 1, the Am79C976 controller will not start
transmitting the preamble for a packet until the Transmit Start Point (CTRL1, bits 16-17)
requirement has been met
and
the complete packet has been copied into the transmit FIFO. When
the NOUFLO bit is cleared to 0, the Transmit Start Point is the only restriction on when preamble
transmission begins for transmit packets.
Setting the NOUFLO bit guarantees that the Am79C976 controller will never suffer transmit
underflows, because the arbiter that controls transfers to and from the SSRAM guarantees a worst
case latency on transfers to and from the MAC and Bus Transmit FIFOs such that it will never
underflow if the complete packet has been copied into the Am79C976 controller before packet
transmission begins.
This bit is an alias of BCR18, bit 11. It is included only to allow programming from the EEPROM for
compatibility with legacy software.
相關(guān)PDF資料
PDF描述
AM79C976KIW PCnet-PRO⑩ 10/100 Mbps PCI Ethernet Controller
AM79C976KCW PCnet-PRO⑩ 10/100 Mbps PCI Ethernet Controller
AM79C978AKCW Single-Chip 1/10 Mbps PCI Home Networking Controller
AM79C978AVCW Single-Chip 1/10 Mbps PCI Home Networking Controller
AM79C978 Single-Chip 1/10 Mbps PCI Home Networking Controller
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
AM79C976KC 制造商:Rochester Electronics LLC 功能描述:METRIC PLASTIC QUAD-RING - Bulk
AM79C976KCW 制造商:AMD 制造商全稱:Advanced Micro Devices 功能描述:PCnet-PRO⑩ 10/100 Mbps PCI Ethernet Controller
AM79C976KD 制造商:Advanced Micro Devices 功能描述:ETHERNET:MEDIA ACCESS CONTROLLER (MAC)
AM79C976KF 制造商:Advanced Micro Devices 功能描述:Ethernet CTLR Single Chip 10Mbps/100Mbps 3.3V 208-Pin PQFP 制造商:AMD (Advanced Micro Devices) 功能描述:Ethernet CTLR Single Chip 10Mbps/100Mbps 3.3V 208-Pin PQFP
AM79C976KI 制造商:Advanced Micro Devices 功能描述:Ethernet CTLR Single Chip 10Mbps/100Mbps 3.3V 208-Pin PQFP 制造商:AMD (Advanced Micro Devices) 功能描述:Ethernet CTLR Single Chip 10Mbps/100Mbps 3.3V 208-Pin PQFP