- 您现在的位置：买卖IC网 > PDF目录69340 > SCD223110QCD (INTEL CORP) 2 CHANNEL(S), 256K bps, SERIAL COMM CONTROLLER, PQFP100 PDF资料下载
参数资料
| 型号： | SCD223110QCD |
| 厂商： | INTEL CORP |
| 元件分类： | 微控制器/微处理器 |
| 英文描述： | 2 CHANNEL(S), 256K bps, SERIAL COMM CONTROLLER, PQFP100 |
| 封装： | METRIC, QFP-100 |
| 文件页数： | 147/178页 |
| 文件大小： | 2247K |
| 代理商： | SCD223110QCD |
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页第120页第121页第122页第123页第124页第125页第126页第127页第128页第129页第130页第131页第132页第133页第134页第135页第136页第137页第138页第139页第140页第141页第142页第143页第144页第145页第146页当前第147页第148页第149页第150页第151页第152页第153页第154页第155页第156页第157页第158页第159页第160页第161页第162页第163页第164页第165页第166页第167页第168页第169页第170页第171页第172页第173页第174页第175页第176页第177页第178页
CD2231 — Intelligent Two-Channel LAN and WAN Communications Controller
70
Datasheet
6.2.4
Transparency
Transparency means that there is a protocol method to prevent confusion and ambiguity between
control characters and data characters in the frame.
For PPP mode, there is a control-escape mechanism. Specific characters are identified as ‘control
mapped’ characters. The control map is called the ACCM (async-control-character map).
Whenever there is a mapped character in the data stream, the transmitter precedes that character
with a control-escape character of 7D. After the control-escape, the character itself is transmitted
with bit 6 inverted. For example, if the character 13 is a mapped character, then the transmission of
13 is 7D–33.
When the receiver sees the 7D control-escape character, the 7D is removed and bit 6 of the
following character is inverted. The resultant reconstructed character is passed on to the host as one
received character.
6.2.4.1
Mapped Characters from 00–1F
When a channel is selected for PPP mode, two ACCMs are assigned. Each ACCM consists of four
registers (32 bits) to define mapped characters in the range 00–1F. One ACCM is for the
transmitter (TXACCM), and one for the receiver (RXACCM). Each bit within the ACCM points to
a particular character within the range. When the bit is set, that character is a mapped character.
When the bit is clear, that character is not a mapped character.
For example, suppose the TXACCM bit pointing to the character 12 is set, and that the TXACCM
bit pointing to the character 0B is clear. Then whenever a 12 is present for transmission, the actual
transmission is 7D–32. Whenever a 0B is present for transmission, the 0B is transmitted without
modification.
Continuing the example, if the receiver ACCM bits pointing to 12 and 0B are also set and clear,
respectively. Then a received 12 (without a preceding 7D) is discarded, and a received 0B (without
a preceding 7D) is passed through to the host unchanged.
6.2.4.2
Mapped Characters from 20 and Above
Three characters above 20 can be mapped. These characters are defined in the Channel Specific
registers TSPMAP[1], TSPMAP[2], and TSPMAP[3].
6.2.4.3
Characters 7D and 7E as Transmitted Data
Whenever the transmitter sees either 7D or 7E as data for transmission, the transmitter treats these
as mapped characters. Thus, a 7D as data is transmitted as 7D–5D, and a 7E as data is transmitted
as 7D–5E.
6.2.4.4
Mapped Characters in the FCS Field
Whenever the transmitter sees that the FCS result to be transmitted contains a mapped character, it
handles that character as any other mapped character. See Section 5.2.4.
For example, if an FCS field is A7–7E, the transmitter would send three characters in the FCS
field, A7–7D–5E. The receiver would convert the received FCS back to A7–7E before completing
the FCS computation.
相关PDF资料 |
PDF描述 |
|---|---|
| SCDV5540 | 5X5 DOT MATRIX DISPLAY, RED, 3.2 mm |
| SCDV5541 | 5X5 DOT MATRIX DISPLAY, YELLOW, 3.2 mm |
| SCDV5543 | 5X5 DOT MATRIX DISPLAY, GREEN, 3.2 mm |
| SCF5249LAG120 | 32-BIT, 120 MHz, RISC PROCESSOR, PQFP144 |
| SCF5250CAG120 | 32-BIT, 120 MHz, MICROPROCESSOR, PQFP144 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| SCD224K122A324F | 制造商:Cornell Dubilier Electronics 功能描述:FILM CAPACITOR |
| SCD224K122A3Z25 | 制造商:Cornell Dubilier Electronics 功能描述:Cap Film 0.22uF 1200V PP 10% (46.99 X 24.6 X 24.1mm) Screw Mount |
| SCD224K122A3Z25-F | 功能描述:薄膜电容器 1200Vdc .22uF 580Vac RoHS:否 制造商:Cornell Dubilier 产品类型: 电介质:Polyester 电容:0.047 uF 容差:10 % 电压额定值:100 V 系列:225P 工作温度范围:- 55 C to + 85 C 端接类型:Radial 引线间隔:9.5 mm |
| SCD224K162A3-24 | 制造商:Cornell Dubilier Electronics 功能描述:FILM CAPACITOR |
| SCD224K162A324F | 制造商:Cornell Dubilier Electronics 功能描述:FILM CAPACITOR |
发布紧急采购，3分钟左右您将得到回复。