參數(shù)資料
型號: CD1865
廠商: Intel Corp.
英文描述: Intelligent Eight-Channel Communications Controller
中文描述: 智能八通道通信控制器
文件頁數(shù): 79/150頁
文件大小: 871K
代理商: CD1865
Intelligent Eight-Channel Communications Controller
CD1865
Datasheet
79
However, when the system software design chooses to make use of the automatic Out-of-Band
Flow Control with the pins, then the signal naming convention no longer holds true in some cases,
depending on whether the device is used as DCE or DTE. In this case, it is best to think of the pins
in terms of their actual uses within the CD1865 and connect them accordingly, without regard to
their names. The RTS* and CTS* pins are associated with the transmitter and the DTR* and DSR*
pins are associated with the receiver. The table below shows Intel
s recommended signal hook-up if
automatic, Out-of-Band Flow Control is required.
For example, if the CD1865 is designed to be a DCE and automatic Out-of-Band Flow Control is
required, the pin labeled DTR should be connected to remote CTS input. If the CD1865 is to be
used as the DTE side, then the CD1865 CTS output would be connected to the remote CTS input.
Note that if automatic Out-of-Band Flow Control is implemented, the activity of DTR and DSR
pins do not implement the function assigned to those signal names by the signalling conventions of
the CCITT and other standards organization. These names would only apply to these pins if they
are under program control and not under automatic CD1865 control. In fact, the
DTR
function, as
defined, enables the modem to go on- and off-line, depending on the state of the pin. If automatic
control is used, then DTR would go inactive when the receive FIFO reached the programmed
threshold thus causing the modem to drop the connection (carrier) to the remote, which would not
be the correct function. Refer to
Section 7.3
for details on operation of modem pins in flow-control
applications.
Modem pins are implemented as I/O ports accessible by either the CD1865 processor or the host.
The modem pins are not connected directly to the transmit or receive hardware. When a user
programs out-of-band modem functions to be active, the CD1865 processor reads from and writes
to these pins. Specifically, when RTS* and CTS* are being used for transmit flow control, the
CD1865 processor asserts RTS* and senses CTS*, as required. Likewise, when configured to do
so, the Receive FIFO negates DTR* when full. The host should not be allowed to re-assert it
inadvertently. The host is not
locked out
of accessing these bits; care should be taken so that these
bits are not written to, causing the system to malfunction.
The user has direct control over the RTS* and DTR* Outputs and can sense the state of CTS*,
CD*, and DSR* Inputs through the Modem Signal Value register (MSVR). Since the host is
accessing these pins directly, there is no delay in the host's ability to detect a level change. DTR*
and CD* depend on the state of the DTRSEL input.
DCE
DTE
CD1865 Pins
Out-of-Band Flow Control
CTS
DTR
Signal remote to transmit
RTS
Not implemented in this direction
RTS
RTS
Request remote permission to transmit
CTS
CTS
Enable transmitter
Modem
Control Pins
Function
RTS*
Request to Send (general-purpose output)
CTS*
Clear to Send (general-purpose input)
DTR*
Data Terminal Ready (carrier detect/general-
purpose input/output)
DSR*
Data Set Ready (general-purpose input)
CD*
Carrier Detect (general-purpose input)
相關(guān)PDF資料
PDF描述
CD22100 CMOS 4 x 4 Crosspoint Switch with Control Memory High-Voltage Type (20V Rating)
CD22100E CMOS 4 x 4 Crosspoint Switch with Control Memory High-Voltage Type (20V Rating)
CD22100F CMOS 4 x 4 Crosspoint Switch with Control Memory High-Voltage Type (20V Rating)
CD22101 CMOS 4 x 4 x 2 Crosspoint Switch with Control Memory
CD22101E CMOS 4 x 4 x 2 Crosspoint Switch with Control Memory
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
CD1865N 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC
CD1865P 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC
CD1866N 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC
CD1866P 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC
CD1867N 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Analog IC