參數(shù)資料
型號(hào): SP502
英文描述: Multi-Mode Serial Transceiver
中文描述: 多模式串行收發(fā)器
文件頁(yè)數(shù): 20/32頁(yè)
文件大?。?/td> 345K
代理商: SP502
Rev. 7/21/03
SP502 Multi-Mode Serial Transceiver
20
Copyright 2003 Sipex Corporation
APPLICATION EXAMPLE
The example application that follows is a fully
configured serial I/O channel in a DTE configu-
ration. The example is comprised of the follow-
ing functional elements:
Processor
SCC
SP502
Mode Select Register (R0[WR])
RL & LL Control Bit Register (R1[WR])
RI Status Bit Register (R1[RD])
Address Decode Logic
Baud Rate Clock Source
I/O Connector Interface
Each of the elements of the application example
are described below. Please refer to
Figure13
.
Processor
The example schematic shows a generic 8-bit
processor connected to a generic SCC. The
processor is also connected to three registers.
The registers are described in further detail
below.
Address Decode Logic
The address decode logic is connected to the
Processor control and address busses and pro-
vides the logic necessary to decode the I/O read
and write operations for the SCC, Mode Select
Register, RL and LL Control Bit Register and
the RI Status Bit Register.
SCC
The SCC provides the I/O functions for a single
serial channel. The SCC is connected to the
Processor I/O bus and is programmed by the
user software. The SCC’s TTL-level serial I/O
pins are connected to the corresponding
TTL-level serial I/O pins on the
SP502
.
SP502
The
SP502
provides buffering and translation
from TTL levels to the selected physical level
interface standard, such as RS-232, V.35, etc.
The physical level interface pins are connected
to a standard 25 pin D-subminiature connector
wired in a DTE configuration with the pin as-
signments corresponding to the EIA-530 speci-
fication. This choice was purely arbitrary. How-
ever, it provides all the necessary signals to
support standards other than EIA-530, such as
V.35, RS-232, RS-449, etc. with an appropriate
cable adapter.
The
SP502
driver and receiver modes are inde-
pendently configured by programming the
SP502
’s RDEC and TDEC input pins. In the
example, the pins are driven by the Mode Select
Register with a programmed value stored by the
user’s software.
Since the
SP502
is shown in a DTE configura-
tion, the example assumes that any synchronous
interface clocking will be provided by the at-
tached DCE device. Consequently, the ST/TT
pin is tied to +5V, thus causing the
SP502
to
receive the transmit clock on the TT(a) and
TT(b) input pins and output the transmit clock to
the SCC on the RxT output pin. The receive
clock is input to the
SP502
on the RT(a) and
RT(b) pins and output to the SCC on the RxC
pin.
Mode Select Register
The mode select register is an 8-bit latch at-
tached to the Processor data bus. The Processor,
under user-software control, can program the
Mode Select Register with the appropriate val-
ues to select the
SP502
’s driver and receiver
modes.
The table shown on the schematic below the
register lists the values for programming the
register to drive the RDEC and TDEC pins on
the
SP502
for the desired physical level inter-
face. The receivers and drivers can be pro-
grammed independently, but in this example the
Mode Select Register must be programmed with
both the RDEC and TDEC values at the same
time. This is because the RDEC and TDEC pins
are driven from the same 8-bit latch.
Note that selecting modes for TDEC that are
shown in the table as undefined will result in the
drivers operating in an undefined mode and
should not be used. Likewise, selecting modes
for RDEC that are shown in the table as unde-
fined will result in indeterminate logic levels
present on the TTL outputs of the
SP502
. Unde-
fined RDEC or TDEC values should never be
programmed.
相關(guān)PDF資料
PDF描述
SP502CF Multi-Mode Serial Transceiver
SP502CM Multi-Mode Serial Transceiver
SP503 Multiprotocol Transceiver
SP503AN Application Note
SP503CF Multiprotocol Transceiver
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
SP5020 制造商:RIEDON 功能描述:
SP5024 制造商:ZARLINK 制造商全稱(chēng):Zarlink Semiconductor Inc 功能描述:3-Wire Bus Controlled Synthesiser
SP5024DP 制造商:ZARLINK 制造商全稱(chēng):Zarlink Semiconductor Inc 功能描述:3-Wire Bus Controlled Synthesiser
SP5024SMP 制造商:ZARLINK 制造商全稱(chēng):Zarlink Semiconductor Inc 功能描述:3-Wire Bus Controlled Synthesiser
SP5025 制造商:未知廠(chǎng)家 制造商全稱(chēng):未知廠(chǎng)家 功能描述:Thermoelectric Cooler