- 您现在的位置：买卖IC网 > PDF目录97867 > DS21Q42TN (DALLAS SEMICONDUCTOR) DATACOM, FRAMER, PQFP128 PDF资料下载
参数资料
| 型号： | DS21Q42TN |
| 厂商： | DALLAS SEMICONDUCTOR |
| 元件分类： | Digital Transmission Controller |
| 英文描述： | DATACOM, FRAMER, PQFP128 |
| 封装： | TQFP-128 |
| 文件页数： | 94/119页 |
| 文件大小： | 1309K |
| 代理商： | DS21Q42TN |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页当前第94页第95页第96页第97页第98页第99页第100页第101页第102页第103页第104页第105页第106页第107页第108页第109页第110页第111页第112页第113页第114页第115页第116页第117页第118页第119页
DS21Q42
76 of 119
17.
TRANSMIT TRANSPARENCY
Each of the 24 T1 channels in the transmit direction of the framer can be either forced to be transparent or
in other words, can be forced to stop Bit 7 Stuffing and/or Robbed Signaling from overwriting the data in
the channels. Transparency can be invoked on a channel by channel basis by properly setting the TTR1,
TTR2, and TTR3 registers.
TTR1/TTR2/TTR3: TRANSMIT TRANSPARENCY REGISTER
(Address=39 to 3B Hex)
(MSB)
(LSB)
CH8
CH7
CH6
CH5
CH4
CH3
CH2
CH1
TTR1 (39)
CH16
CH15
CH14
CH13
CH12
CH11
CH10
CH9
TTR2 (3A)
CH24
CH23
CH22
CH21
CH20
CH19
CH18
CH17
TTR3 (3B)
SYMBOLS
POSITIONS
NAME AND DESCRIPTION
CH1-24
TTR1.0-3.7
Transmit Transparency Registers.
0 = this DS0 channel is not transparent
1 = this DS0 channel is transparent
Each of the bit position in the Transmit Transparency Registers (TTR1/TTR2/TTR3) represent a DS0
channel in the outgoing frame. When these bits are set to a one, the corresponding channel is transparent
(or clear). If a DS0 is programmed to be clear, no robbed bit signaling will be inserted nor will the
channel have Bit 7 stuffing performed. However, in the D4 framing mode, bit 2 will be overwritten by a
zero when a Yellow Alarm is transmitted. Also the user has the option to prevent the TTR registers from
determining which channels are to have Bit 7 stuffing performed. If the TCR2.0 and TCR1.3 bits are set
to one, then all 24 T1 channels will have Bit 7 stuffing performed on them regardless of how the TTR
registers are programmed. In this manner, the TTR registers are only affecting which channels are to have
robbed bit signaling inserted into them. Please see Figure 20-15 for more details.
18.
INTERLEAVED PCM BUS OPERATION
In many architectures, the outputs of individual framers are combined into higher speed serial buses to
simplify transport across the system. The DS21Q42 can be configured to allow each framer’s data and
signaling busses to be multiplexed into higher speed data and signaling busses eliminating external
hardware saving board space and cost.
The interleaved PCM bus option supports two bus speeds and interleave modes. The 4.096 MHz bus
speed allows two framers to share a common bus. The 8.192 MHz bus speed allows all four of the
DS21Q42’s framers to share a common bus. Framers can interleave their data either on byte or frame
boundaries. Framers that share a common bus must be configured through software and require several
device pins to be connected together externally (see figures 18-1 & 18-2). Each framer’s elastic stores
must be enabled and configured for 2.048 MHz operation. The signal RSYNC must be configured as an
input on each framer.
相关PDF资料 |
PDF描述 |
|---|---|
| DS21Q42T | DATACOM, FRAMER, PQFP128 |
| DS21Q43AT | DATACOM, FRAMER, PQFP128 |
| DS21Q44T | DATACOM, FRAMER, PQFP128 |
| DS21Q44TN | DATACOM, FRAMER, PQFP128 |
| DS21Q48N | DATACOM, PCM TRANSCEIVER, PBGA144 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| DS21Q43A | 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:Quad E1 Framer |
| DS21Q43AT | 功能描述:网络控制器与处理器 IC Quad E1 Framer RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流（最大值）:595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray |
| DS21Q43AT+ | 功能描述:网络控制器与处理器 IC Quad E1 Framer RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流（最大值）:595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray |
| DS21Q43ATN | 制造商:DALLAS 制造商全称:Dallas Semiconductor 功能描述:Quad E1 Framer |
| DS21Q43-ATN | 功能描述:网络控制器与处理器 IC Quad E1 Framer RoHS:否 制造商:Micrel 产品:Controller Area Network (CAN) 收发器数量: 数据速率: 电源电流（最大值）:595 mA 最大工作温度:+ 85 C 安装风格:SMD/SMT 封装 / 箱体:PBGA-400 封装:Tray |
发布紧急采购，3分钟左右您将得到回复。