參數(shù)資料
型號(hào): MC68838FCC
廠商: MOTOROLA INC
元件分類: 微控制器/微處理器
英文描述: 1 CHANNEL(S), 125M bps, FDDI CONTROLLER, CQFP120
封裝: CERAMIC, QFP-120
文件頁(yè)數(shù): 70/100頁(yè)
文件大小: 465K
代理商: MC68838FCC
MOTOROLA
MC68838 USER’S MANUAL
8-1
SECTION 8
TRANSMIT DATA PATH OPERATION
The receive data path portion and transmit data path portion of the MAC work
independently of each other except for signals that must be passed between the two
sections of the device. In fact, the receive data path portion does not receive any signals
from the transmit data path portion. The signals that the transmit data path portion
receives from the receive data path portion are as follows:
The transmitter FSM receives 11 event signals from the receiver FSM as described
in the FDDI MAC standard. In addition, it uses the current values of the frame status
flags.
The timer logic block receives an enable/disable TVX signal and a reset TVX timer
signal from the receiver FSM. In addition, the timer logic block can set the T_BID_RC
register field within itself via a connection to the receive data path.
The repeat function is connected to the receive data path that can read the status
fIags.
The address and target request time register block within the address and target
request time comparison logic can be selected to transmit my short address register,
my long address register, or target request time (via the TX MUX) to the PHY (ELM)
when the MAC sends either special void frames or internally generated claim and
beacon frames.
8.1 TRANSMIT DATA PATH CONTROL
The following list summarizes the interpretation of TPATHx as per the state of TXCTL1–
TXCTL0:
00 = FILLER—TPATHx is unspecified.
01 = TX_START—TPATHx contains the first byte of the packet request header. Only
a second TX_START, TX_DATA, or TX_END can follow this.
10= TX_END—TPATHx = AxxxMxxx, where x is don't care. If A = l, then the MAC
should abort the transmission of the packet (i.e., turn it into a fragment by
sending IDLEs); if A = 0, then the MAC should normally end this frame (i.e.,
append CRC, T-symbol, and frame status symbols). When M = 1, the FSI has
more packets ready to send.
11 = TX_DATA—TPATHx contains the second and third byte of the packet request
header or frame data. TX_START can follow this until TXRDY is asserted.
TX_DATA or TX_END can always follow this.
The FSI requests the token by transferring the packet request header to the MAC. The
packet request header, which consists of three bytes of information, is associated with
ARCHIVE
INFORMA
TION
ARCHIVE
INFORMA
TION
相關(guān)PDF資料
PDF描述
MC68EC020FG 32-BIT, 25 MHz, MICROCONTROLLER, PQFP100
MC68HC05CC1P 8-BIT, MROM, 4.2 MHz, MICROCONTROLLER, PDIP40
MC68HC05CC2B 8-BIT, MROM, 4.2 MHz, MICROCONTROLLER, PDIP42
MC68HC05CT4FN 8-BIT, MROM, 2.048 MHz, MICROCONTROLLER, PQCC44
MC68HC05J1P 8-BIT, MROM, 2.1 MHz, MICROCONTROLLER, PDIP20
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MC68840FE25B 制造商:Motorola Inc 功能描述:68840FE25B
MC68840FE-25B 制造商:Motorola Inc 功能描述:68840FE-25B
MC6885 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:HEX THREE-STATE BUFFER/INVERTERS
MC68851 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:32-Bit Paged Memory Management Unit
MC6885L 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:HEX THREE-STATE BUFFER/INVERTERS