MAX29X是美国MAXIM公司生瓣的8阶开关电容低通滤波器,由于价格便宜、使用方便、设计简单，在通讯、信号自理等领域得到了广泛的应用。本文就其工作原理、电气参数、设计注意事项等问题作了讨论，具有一定的实用参考价值。关键词：开关电容、滤波器、设计 1 引言 开关电容滤波器在近些年得到了迅速的发展，世界上一些知名的半导体厂家相继推出了自己的开头电容滤波器集成电路，使形状电容滤波器的发展上了一个新台阶。 MAXIM公司在模拟器件生产领域颇具影响，它生产MAX291/292/293/294/295/296/297系列8阶低通开关电容滤波器由于使用方便（基本上不需外接元件）、设计简单（频率响应函数是固定的，只需确定其拐角频率即截止频率)、尺寸小（有8-pin DIP封装）等优点，在ADC的反混叠滤波、噪声分析、电源噪声抑制等领域得到了广泛的应用。 MAX219/295为巴特活思（型滤波器，在通频带内，它的增益最稳定，波动小，主要用于仪表测量等要求整个通频带内增益恒定的场合。MAX292/296为贝塞尔（Bessel）滤波器，在通频带内它的群时延时恒定的，相位对频率呈线性关系，因此脉冲信号通过MAX292/296之后尖峰幅度小，稳定速度快。由于脉冲信号通过贝塞尔滤波器之后所有频率分量的延迟时间是相同的，故可保证波形基本不变。关于巴特活和贝塞尔滤波器的特性可能图1来说明。图1的踪迹A为加到滤波器输入端的3kHz的脉冲，这里我们把滤波器的截止频率设为10kHZ。踪迹B通过MAX292/296后的波形。从图中可以看出，由于MAX292/296在通带内具有线性相位特性，输出波形基本上保持了方波形状，只是边沿处变圆了一些。方波通过MAX291/295之后，由于不同频率的信号产生的时延不同，输出波形中就出现了尖峰(overshoot)和铃流(ringing)。 MAX293/294/297为8阶圆型（Elliptic）滤波器，它的滚降速度快，从通频带到阻带的过渡带可以作得很窄。在椭圆型滤波器中，第一个传输零点后输出将随频率的变高而增大，直到第二个零点处。这样几番重复就使阻事宾频响呈现波浪形，如图2所示。阻带从fS起算起，高于频率fS处的增益不会超过fS处的增益。在椭圆型滤波中，通频带内的增益存在一定范围的波动。椭圆型滤波器的一个重要参数就是过渡比。过渡比定义为阻带频率fS与拐角频率（有时也等同为截止频率）由时钟频率确定。时钟既可以是外接的时钟，也可以是自己的内部时钟。使用内部时钟时只需外接一个定时用的电容既可。 在MAX29X系列滤波器集成电路中，除了滤波器电路外还有一个独立的运算放大器（其反相输入端已在内部接地）。用这个运算放大器可以组成配合MAX29X系列滤波器使用后的滤波、反混滤波等连续时间低通滤波器。 下面归纳一下它们的特点： ●全部为8阶低通滤波器。MAX291/MAX295为巴特沃思滤波器；MAX292/296为贝塞尔滤波器；MAX293/294/297为椭圆滤波器。 ●通过调整时钟，截止频率的调整范围为：0.1Hz～25kHz（MAX291/292/293*294）；0.1Hz～kHz（MAX295/296/297）。 ●既可用外部时钟也可用内部时钟作为截止频率的控制时钟。 ●时钟频率和截止频率的比率：10∶1(MAX291/292/293/294);50∶1(MAX295/296/297)。 ●既可用单+5V电源供电也可用±5V双电源供电。 ●有一个独立的运算放大器可用于其它应用目的。 ●8-pin DIP、8-pin SO和宽SO-16多种封装。2 管脚排列和主要电气参数 MAX29X系列开头电容滤波器的管脚排列如图3所示。 管脚功能定义如下： CLK：时钟输入。 OP OUT：独立运放的输出端。 OP INT：独立运放的同相输入端。 OUT：滤波器输出。 IN：滤波器输入。 V-：负电源 。双电源供电时搛-2.375～-5.5V之间的电压，单电源供电时V--=-V。 V+：正电源。双电源供电时V+=+2.35～+5.5V,单电源供电时V+=+4.75～+11.0V。 GND：地线。单电源工作时GND端必须用电源电压的一半作偏置电压。 NC：空脚，无连线。 MAX29X的极限电气参数如下： 电源（V+～V-）：12V 输入电压（任意脚）：V--0.3V≤VIN≤V++0.3V 连续工作时的功耗：8脚塑封DIP：727mW；8脚SO：471mW；16脚宽SO：762mW；8脚瓷封DIP：640mW。 工作温度范围：MAX29-C-：0℃～+70℃；MAX29-E-：-40℃～+85℃；MAX29-MJA：-55℃～+125℃；保存温度范围：-65℃～+160℃；焊接温度（10秒）：+300℃； 大多数的形状电容滤波器都采用四节级连结构，每一节包含两个滤波器极点。这种方法的特点就是易于设计。但采用这种方法设计出来的滤波器的特性对所用元件的元件值偏差很敏感。基于以上考虑，MAX29X系列用带有相加和比例功能的开关电容持了梯形无源滤波器，这种方法保持了梯形无源滤波器的优点，在这种结构中每个元件的影响作用是对于整个频率响应曲线的，某元件值的误差将会分散到所有的极点，因此不值像四节级连结构那样对某一个极点特别明显的影响。3 MAX29X的频率特性 MAX29X的频率特性如图4所示。图中的fs都假定为1kHz。4 设计考虑 下面对MAX29X系列形状电容滤波器的使用做些讨论。4.1 时钟信号 MAX29X系列开头电容滤波器推荐使用的时钟信号最高频率为2.5MHz。根据对应的时钟频率和拐角频率的比值，MAX291/MAX292/MAX293/MAX294的拐角频率最高为25kHz.MAX295/MAX296/MAX297的拐角频率最高为50kHz 。 MAX29X系列开关电容滤波器的时钟信号既可幅外部时钟直接驱动也可由内部振荡器产生。使用外部时钟时，无论是采用单电源供电还是双电源供电，CLK可直接和采用+5V供电的CMOS时钟信号发生器的输出相连。通过调整外部时钟的频率，可完成滤波器拐角的实时调整。 当使用内部时钟时，振荡器的频率由接在CLK端上的电容VCOSC决定： fCOSC (kHz)=105/3COSC (pF) 4.2 供电 MAX29X系列开关电容滤波器既可用单电源工作也可用双电源工作。双电源供电时的电源电压范围为±2.375～±5.5V。在实际电路中一般要在正负电源和GND之间接一旁路电容。 当采用单电源供电时，V-端接地，而GND端要通过电阻分压获得一个电压参考，该电压参考的电压值为1/2的电源电压，参见图5。4.3 输入信号幅度范围限制 MAX29X允许的输入信号的最大范围为V--0.3V～V++0.3V。一般情况下在+5V单电源供电时输入信号范围取1V～4V,±5V双电源供电时，输入信号幅度范围取±4V。如果输入信号超过此范围，总谐波失真THD和噪声就大大增加；同样如果输入信号幅度过小（VP-P＜1V），也会造成THD和噪声的增加。4.4 独立运算放大器的用法 MAX29X中都设计有一个独立的运算放大器，这个放大器和滤波器的实现无直接关系，用这个放大器可组成一个一阶和二阶滤波器，用于实现MAX29X之前的反混叠滤波功能鄞MAX29X之后的时钟噪声抑制功能。这个运算放大器的反相端已在内部和GND相连。 图6是用该独立运放组成的2阶低通滤波器的电路，它的拐角频率为10kHz,输入阻抗为22Ω,可满足MAX29X形状电容滤波器的最小负载要求（MAX29X的输出负载要求不小于20kΩ）可以通过改变R1、R2、R3、C1、C2的元件值改变拐角频率。具体的元件值和拐角频率的对应关系参见表1。
上传时间： 2013-10-18
上传用户：macarco
WHAT MIME64 IS: MIME64 is an encoding described in RFC1341 as MIME base64.Its purpose is to encode binary files into ASCII so that they may be passedthrough e-mail gates. In this regard, MIME64 is similar to UUENCODE.Although most binaries these days are transmitted using UUENCODE, Ihave seen a few using MIME64, and I have had requests from friends thatI decode MIME64 files that have fallen into their hands. As long assome MIME64 continues to exist, a package such as this one is usefulto have.
标签： MIME described 64 encoding
上传时间： 2013-12-17
上传用户：maizezhen
The "GEE! It s Simple" package illustrates Gaussian elimination with partial pivoting, which produces a factorization of P*A into the product L*U where P is a permutation matrix, and L and U are lower and upper triangular, respectively. The functions in this package are accurate, but they are far slower than their MATLAB equivalents (x=A\b, [L,U,p]=lu(A), and so on). They are presented here merely to illustrate and educate. "Real" production code should use backslash and lu, not this package.
标签： illustrates elimination Gaussian pivoting
上传时间： 2016-11-09
上传用户：wang5829
The "GEE! It s Simple" package illustrates Gaussian elimination with partial pivoting, which produces a factorization of P*A into the product L*U where P is a permutation matrix, and L and U are lower and upper triangular, respectively. The functions in this package are accurate, but they are far slower than their MATLAB equivalents (x=A\b, [L,U,p]=lu(A), and so on). They are presented here merely to illustrate and educate. "Real" production code should use backslash and lu, not this package.
标签： illustrates elimination Gaussian pivoting
上传时间： 2014-01-21
上传用户：lxm
We analyze, both analytically and numerically, the effectiveness of cloaking an infinite cylinder from observations by electromagnetic waves in three dimensions. We show that, as truncated approximations of the ideal permittivity and permeability tensors tend towards the singular ideal cloaking fields, so that the anisotropy ratio tends to infinity, the D and B fields blow up near the cloaking surface. Since the metamaterials used to implement cloaking are based on effective medium theory, the resulting large variation in D and B will pose a challenge to the suitability of the field averaged characterization of " and 碌. We also consider cloaking with and without the SHS (softand- hard surface) lining, shown in [6] to be theoretically necessary for cloaking in the cylindrical geometry. We demonstrate numerically that cloaking is significantly improved by the SHS lining, with both the far field of the scattered wave significantly reduced and the blow up of D and B prevented.
标签： effectiveness analytically numerically cloaking
上传时间： 2017-03-30
上传用户：zxc23456789
GRE 数学圣经，下面是详细的英文介绍： Comprehensive Prep for GRE Math Every year, students pay $1,000 and more to test prep companies to prepare for the math section of the GRE. Now you can get the same preparation in a book. Although the GRE math section is difficult, it is very learnable. GRE Math Bible presents a thorough analysis of GRE math and introduces numerous analytic techniques that will help you immensely, not only on the GRE but in graduate school as well.
标签： GRE Math 数学
上传时间： 2015-08-22
上传用户：东大寺的
/* ********************************************************************************************************* * uC/TCP-IP V2 * The Embedded TCP/IP Suite * * (c) Copyright 2003-2010; Micrium, Inc.; Weston, FL * * All rights reserved. Protected by international copyright laws. * * uC/TCP-IP is provided in source form to registered licensees ONLY. It is * illegal to distribute this source code to any third party unless you receive * written permission by an authorized Micrium representative. Knowledge of * the source code may NOT be used to develop a similar product. * * Please help us continue to provide the Embedded community with the finest * software available. Your honesty is greatly appreciated. * * You can contact us at www.micrium.com. ********************************************************************************************************* */ /* ********************************************************************************************************* * * NETWORK TCP LAYER * (TRANSMISSION CONTROL PROTOCOL) * * Filename : net_tcp.h * Version : V2.10 * Programmer(s) : ITJ ********************************************************************************************************* * Note(s) : (1) Supports Transmission Control Protocol as described in RFC #793 with the following * restrictions/constraints : * * (a) TCP Security & Precedence NOT supported RFC # 793, Section 3.6 * * (b) TCP Urgent Data NOT supported RFC # 793, Section 3.7 * 'The Communication of * Urgent Information' * * (c) The following TCP options NOT supported : * * (1) Window Scale RFC #1072, Section 2 * RFC #1323, Section 2 * (2) Selective Acknowledgement (SACK) RFC #1072, Section 3 * RFC #2018 * RFC #2883 * (3) TCP Echo RFC #1072, Section 4 * (4) Timestamp RFC #1323, Section 3.2 * (5) Protection Against Wrapped Sequences (PAWS) RFC #1323, Section 4 * * (d) #### IP-Options-to-TCP-Connection RFC #1122, Section 4.2.3.8 * Handling NOT supported * * (e) #### ICMP-Error-Message-to-TCP-Connection RFC #1122, Section 4.2.3.9 * Handling NOT currently supported * * (2) TCP Layer assumes/requires Network Socket Layer (see 'net_sock.h MODULE Note #1a2'). ********************************************************************************************************* */ /*$PAGE*/ /* ********************************************************************************************************* * MODULE * * Note(s) : (1) TCP Layer module is NOT required for UDP-to-Application API configuration. * * See also 'net_cfg.h TRANSPORT LAYER CONFIGURATION' * & 'net_cfg.h USER DATAGRAM PROTOCOL LAYER CONFIGURATION'. * * See also 'net_tcp.h Note #2'. * * (2) The following TCP-module-present configuration value MUST be pre-#define'd in * 'net_cfg_net.h' PRIOR to all other network modules that require TCP Layer * configuration (see 'net_cfg_net.h TCP LAYER CONFIGURATION Note #2b') : * * NET_TCP_MODULE_PRESENT ********************************************************************************************************* */ #ifdef NET_TCP_MODULE_PRESENT /* See Note #2. */ /* ********************************************************************************************************* * EXTERNS ********************************************************************************************************* */ #if ((defined(NET_TCP_MODULE)) && \ (defined(NET_GLOBALS_EXT))) #define NET_TCP_EXT #else #define NET_TCP_EXT extern #endif /*$PAGE*/ /* ********************************************************************************************************* * DEFINES ********************************************************************************************************* */ /* ********************************************************************************************************* * TCP HEADER DEFINES * * Note(s) : (1) The following TCP value MUST be pre-#define'd in 'net_def.h' PRIOR to 'net_buf.h' so that * the Network Buffer Module can configure maximum buffer header size (see 'net_def.h TCP * LAYER DEFINES' & 'net_buf.h NETWORK BUFFER INDEX & SIZE DEFINES Note #1') : * * (a) NET_TCP_HDR_SIZE_MAX 60 (NET_TCP_HDR_LEN_MAX * * NET_TCP_HDR_LEN_WORD_SIZE) * * (2) Urgent pointer & data NOT supported (see 'net_tcp.h Note #1b'). ********************************************************************************************************* */ #define NET_TCP_HDR_LEN_MASK 0xF000u #define NET_TCP_HDR_LEN_SHIFT 12u #define NET_TCP_HDR_LEN_NONE 0u #define NET_TCP_HDR_LEN_MIN 5u #define NET_TCP_HDR_LEN_MAX 15u #define NET_TCP_HDR_LEN_WORD_SIZE CPU_WORD_SIZE_32 #define NET_TCP_HDR_SIZE_MIN (NET_TCP_HDR_LEN_MIN * NET_TCP_HDR_LEN_WORD_SIZE) #if 0 /* See Note #1a. */ #define NET_TCP_HDR_SIZE_MAX (NET_TCP_HDR_LEN_MAX * NET_TCP_HDR_LEN_WORD_SIZE) #endif #define NET_TCP_HDR_SIZE_TOT_MIN (NET_IP_HDR_SIZE_TOT_MIN + NET_TCP_HDR_SIZE_MIN) #define NET_TCP_HDR_SIZE_TOT_MAX (NET_IP_HDR_SIZE_TOT_MAX + NET_TCP_HDR_SIZE_MAX) #define NET_TCP_PSEUDO_HDR_SIZE 12u /* = sizeof(NET_TCP_PSEUDO_HDR) */ #define NET_TCP_PORT_NBR_RESERVED NET_PORT_NBR_RESERVED #define NET_TCP_PORT_NBR_NONE NET_TCP_PORT_NBR_RESERVED #define NET_TCP_HDR_URG_PTR_NONE 0x0000u /* See Note #2. */ /*$PAGE*/ /* ********************************************************************************************************* * TCP HEADER FLAG DEFINES * * Note(s) : (1) See 'TCP HEADER Note #2' for flag fields. * * (2) Urgent pointer & data NOT supported (see 'net_tcp.h Note #1b'). ********************************************************************************************************* */ #define NET_TCP_HDR_FLAG_MASK 0x0FFFu #define NET_TCP_HDR_FLAG_NONE DEF_BIT_NONE #define NET_TCP_HDR_FLAG_RESERVED 0x0FE0u /* MUST be '0'. */ #define NET_TCP_HDR_FLAG_URGENT DEF_BIT_05 /* See Note #2. */ #define NET_TCP_HDR_FLAG_ACK DEF_BIT_04 #define NET_TCP_HDR_FLAG_PUSH DEF_BIT_03 #define NET_TCP_HDR_FLAG_RESET DEF_BIT_02 #define NET_TCP_HDR_FLAG_SYNC DEF_BIT_01 #define NET_TCP_HDR_FLAG_FIN DEF_BIT_00 #define NET_TCP_HDR_FLAG_CLOSE NET_TCP_HDR_FLAG_FIN /* ********************************************************************************************************* * TCP FLAG DEFINES ********************************************************************************************************* */ /* ------------------ NET TCP FLAGS ------------------- */ #define NET_TCP_FLAG_NONE DEF_BIT_NONE #define NET_TCP_FLAG_USED DEF_BIT_00 /* TCP conn cur used; i.e. NOT in free TCP conn pool. */ /* ------------------ TCP TX FLAGS ------------------- */ /* TCP tx flags copied from TCP hdr flags. */ #define NET_TCP_FLAG_TX_FIN NET_TCP_HDR_FLAG_FIN #define NET_TCP_FLAG_TX_CLOSE NET_TCP_FLAG_TX_FIN #define NET_TCP_FLAG_TX_SYNC NET_TCP_HDR_FLAG_SYNC #define NET_TCP_FLAG_TX_RESET NET_TCP_HDR_FLAG_RESET #define NET_TCP_FLAG_TX_PUSH NET_TCP_HDR_FLAG_PUSH #define NET_TCP_FLAG_TX_ACK NET_TCP_HDR_FLAG_ACK #define NET_TCP_FLAG_TX_URGENT NET_TCP_HDR_FLAG_URGENT #define NET_TCP_FLAG_TX_BLOCK DEF_BIT_07 /* ------------------ TCP RX FLAGS ------------------- */ #define NET_TCP_FLAG_RX_DATA_PEEK DEF_BIT_08 #define NET_TCP_FLAG_RX_BLOCK DEF_BIT_15 /*$PAGE*/ /* ********************************************************************************************************* * TCP TYPE DEFINES * * Note(s) : (1) NET_TCP_TYPE_&&& #define values specifically chosen as ASCII representations of the TCP * types. Memory displays of TCP types will display with their chosen ASCII names. ********************************************************************************************************* */ /* ------------------ NET TCP TYPES ------------------- */ #if (CPU_CFG_ENDIAN_TYPE == CPU_ENDIAN_TYPE_BIG) #define NET_TCP_TYPE_NONE 0x4E4F4E45u /* "NONE" in ASCII. */ #define NET_TCP_TYPE_CONN 0x54435020u /* "TCP " in ASCII. */ #else #if (CPU_CFG_DATA_SIZE == CPU_WORD_SIZE_32) #define NET_TCP_TYPE_NONE 0x454E4F4Eu /* "NONE" in ASCII. */ #define NET_TCP_TYPE_CONN 0x20504354u /* "TCP " in ASCII. */ #elif (CPU_CFG_DATA_SIZE == CPU_WORD_SIZE_16) #define NET_TCP_TYPE_NONE 0x4F4E454Eu /* "NONE" in ASCII. */ #define NET_TCP_TYPE_CONN 0x43542050u /* "TCP " in ASCII. */ #else /* Dflt CPU_WORD_SIZE_08. */ #define NET_TCP_TYPE_NONE 0x4E4F4E45u /* "NONE" in ASCII. */ #define NET_TCP_TYPE_CONN 0x54435020u /* "TCP " in ASCII. */ #endif #endif /* ********************************************************************************************************* * TCP SEQUENCE NUMBER DEFINES * * Note(s) : (1) TCP initial transmit sequence number is incremented by a fixed value, preferably a large * prime value or a large value with multiple unique factors. * * (a) One reasonable TCP initial transmit sequence number increment value example : * * 65527 = 37 * 23 * 11 * 7 * * * #### NET_TCP_TX_SEQ_NBR_CTR_INC could be developer-configured in 'net_cfg.h'. * * See also 'NET_TCP_TX_GET_SEQ_NBR() Notes #1b2 & #1c2'. ********************************************************************************************************* */ #define NET_TCP_SEQ_NBR_NONE 0u #define NET_TCP_ACK_NBR_NONE NET_TCP_SEQ_NBR_NONE #define NET_TCP_TX_SEQ_NBR_CTR_INC 65527u /* See Note #1. */ #define NET_TCP_ACK_NBR_DUP_WIN_SIZE_SCALE 4 /*$PAGE*/ /* ********************************************************************************************************* * TCP DATA/TOTAL LENGTH DEFINES * * Note(s) : (1) (a) TCP total length #define's (NET_TCP_TOT_LEN) relate to the total size of a complete * TCP packet, including the packet's TCP header. Note that a complete TCP packet MAY * be fragmented in multiple Internet Protocol packets. * * (b) TCP data length #define's (NET_TCP_DATA_LEN) relate to the data size of a complete * TCP packet, equal to the total TCP packet length minus its TCP header size. Note * that a complete TCP packet MAY be fragmented in multiple Internet Protocol packets. ********************************************************************************************************* */ /* See Notes #1a & #1b. */ #define NET_TCP_DATA_LEN_MIN 0u #define NET_TCP_TOT_LEN_MIN (NET_TCP_HDR_SIZE_MIN + NET_TCP_DATA_LEN_MIN) #define NET_TCP_TOT_LEN_MAX (NET_IP_TOT_LEN_MAX - NET_IP_HDR_SIZE_MIN ) #define NET_TCP_DATA_LEN_MAX (NET_TCP_TOT_LEN_MAX - NET_TCP_HDR_SIZE_MIN) /*$PAGE*/ /* ********************************************************************************************************* * TCP SEGMENT SIZE DEFINES * * Note(s) : (1) (a) RFC # 879, Section 3 states that the TCP Maximum Segment Size "counts only * data octets in the segment, ... not the TCP header or the IP header". * * (b) RFC #1122, Section 4.2.2.6 requires that : * * (1) "The MSS value to be sent in an MSS option must be less than or equal to * * (A) MMS_R - 20 * * where MMS_R is the maximum size for a transport-layer message that can * be received." * * (2) "If an MSS option is not received at connection setup, TCP MUST assume a * default send MSS of 536 (576 - 40)." * * See also 'net_ip.h IP DATA/TOTAL LENGTH DEFINES Note #1'. ********************************************************************************************************* */ /* See Note #1. */ #define NET_TCP_MAX_SEG_SIZE_DFLT (NET_IP_MAX_DATAGRAM_SIZE_DFLT - NET_IP_HDR_SIZE_MIN - NET_TCP_HDR_SIZE_MIN) #define NET_TCP_MAX_SEG_SIZE_DFLT_RX NET_TCP_DATA_LEN_MAX /* See Note #1b1. */ #define NET_TCP_MAX_SEG_SIZE_DFLT_TX NET_TCP_MAX_SEG_SIZE_DFLT /* See Note #1b2. */ #define NET_TCP_MAX_SEG_SIZE_NONE 0u #define NET_TCP_MAX_SEG_SIZE_MIN NET_TCP_MAX_SEG_SIZE_DFLT #define NET_TCP_MAX_SEG_SIZE_MAX NET_TCP_DATA_LEN_MAX #define NET_TCP_SEG_LEN_MIN NET_TCP_DATA_LEN_MIN #define NET_TCP_SEG_LEN_MAX NET_TCP_DATA_LEN_MAX #define NET_TCP_SEG_LEN_SYNC 1u #define NET_TCP_SEG_LEN_FIN 1u #define NET_TCP_SEG_LEN_CLOSE NET_TCP_SEG_LEN_FIN #define NET_TCP_SEG_LEN_ACK 0u #define NET_TCP_SEG_LEN_RESET 0u #define NET_TCP_SEG_LEN_PROBE 0u #define NET_TCP_DATA_LEN_TX_SYNC 0u #define NET_TCP_DATA_LEN_TX_FIN 0u #define NET_TCP_DATA_LEN_TX_CLOSE NET_TCP_DATA_LEN_TX_FIN #define NET_TCP_DATA_LEN_TX_ACK 0u #define NET_TCP_DATA_LEN_TX_PROBE_NO_DATA 0u #define NET_TCP_DATA_LEN_TX_PROBE_DATA 1u #define NET_TCP_DATA_LEN_TX_RESET 0u #define NET_TCP_TX_PROBE_DATA 0x00u /* ********************************************************************************************************* * TCP WINDOW SIZE DEFINES * * Note(s) : (1) Although NO RFC specifies the absolute minimum TCP connection window size value allowed, * RFC #793, Section 3.7 'Data Communication : Managing the Window' states that for "the * window ... there is an assumption that this is related to the currently available data * buffer space available for this connection". ********************************************************************************************************* */ #define NET_TCP_WIN_SIZE_NONE 0u #define NET_TCP_WIN_SIZE_MIN NET_TCP_MAX_SEG_SIZE_MIN #define NET_TCP_WIN_SIZE_MAX DEF_INT_16U_MAX_VAL /*$PAGE*/ /* ********************************************************************************************************* * TCP HEADER OPTIONS DEFINES * * Note(s) : (1) See the following RFC's for TCP options summary : * * (a) RFC # 793, Section 3.1 'Header Format : Options' * (b) RFC #1122; Sections 4.2.2.5, 4.2.2.6 * * (2) TCP option types are encoded in the first octet for each TCP option as follows : * * -------- * | TYPE | * -------- * * The TCP option type value determines the TCP option format : * * (a) The following TCP option types are single-octet TCP options -- i.e. the option type * octet is the ONLY octet for the TCP option. * * (1) TYPE = 0 End of Options List * (2) TYPE = 1 No Operation * * * (b) All other TCP options MUST be multi-octet TCP options (see RFC #1122, Section 4.2.2.5) : * * ------------------------------ * | TYPE | LEN | TCP OPT | * ------------------------------ * * where * TYPE Indicates the specific TCP option type * LEN Indicates the total TCP option length, in octets, including * the option type & the option length octets * TCP OPT Additional TCP option octets, if any, that contain the remaining * TCP option information * * The following TCP option types are multi-octet TCP options where the option's second * octet specify the total TCP option length, in octets, including the option type & the * option length octets : * * (1) TYPE = 2 Maximum Segment Size See RFC # 793, Section 3.1 'Header Format : * Options : Maximum Segment Size'; * RFC #1122, Section 4.2.2.6; * RFC # 879, Section 3 * * (2) TYPE = 3 Window Scale See 'net_tcp.h Note #1c1' * (3) TYPE = 4 SACK Allowed See 'net_tcp.h Note #1c2' * (4) TYPE = 5 SACK Option See 'net_tcp.h Note #1c2' * (5) TYPE = 6 Echo Request See 'net_tcp.h Note #1c3' * (6) TYPE = 7 Echo Reply See 'net_tcp.h Note #1c3' * (7) TYPE = 8 Timestamp See 'net_tcp.h Note #1c4' * * (3) TCP header allows for a maximum option list length of 40 octets : * * NET_TCP_HDR_OPT_SIZE_MAX = NET_TCP_HDR_SIZE_MAX - NET_TCP_HDR_SIZE_MIN * * = 60 - 20 * * = 40 * * (4) 'NET_TCP_OPT_SIZE' MUST be pre-defined PRIOR to all definitions that require TCP option * size data type. ********************************************************************************************************* */ /*$PAGE*/ #define NET_TCP_HDR_OPT_END_LIST 0u #define NET_TCP_HDR_OPT_NOP 1u #define NET_TCP_HDR_OPT_MAX_SEG_SIZE 2u #define NET_TCP_HDR_OPT_WIN_SCALE 3u #define NET_TCP_HDR_OPT_SACK_PERMIT 4u #define NET_TCP_HDR_OPT_SACK 5u #define NET_TCP_HDR_OPT_ECHO_REQ 6u #define NET_TCP_HDR_OPT_ECHO_REPLY 7u #define NET_TCP_HDR_OPT_TS 8u #define NET_TCP_HDR_OPT_PAD NET_TCP_HDR_OPT_END_LIST #define NET_TCP_HDR_OPT_LEN_END_LIST 1u #define NET_TCP_HDR_OPT_LEN_NOP 1u #define NET_TCP_HDR_OPT_LEN_MAX_SEG_SIZE 4u #define NET_TCP_HDR_OPT_LEN_WIN_SCALE 3u #define NET_TCP_HDR_OPT_LEN_SACK_PERMIT 2u #define NET_TCP_HDR_OPT_LEN_ECHO_REQ 6u #define NET_TCP_HDR_OPT_LEN_ECHO_REPLY 6u #define NET_TCP_HDR_OPT_LEN_TS 10u #define NET_TCP_HDR_OPT_LEN_SACK_MIN 6u #define NET_TCP_HDR_OPT_LEN_SACK_MAX 38u #define NET_TCP_HDR_OPT_LEN_MIN 1u #define NET_TCP_HDR_OPT_LEN_MIN_LEN 2u #define NET_TCP_HDR_OPT_LEN_MAX 38u typedef CPU_INT32U NET_TCP_OPT_SIZE; /* TCP opt size data type (see Note #4). */ #define NET_TCP_HDR_OPT_SIZE_WORD (sizeof(NET_TCP_OPT_SIZE)) #define NET_TCP_HDR_OPT_SIZE_MAX (NET_TCP_HDR_SIZE_MAX - NET_TCP_HDR_SIZE_MIN) #define NET_TCP_HDR_OPT_NBR_MIN 0u #define NET_TCP_HDR_OPT_NBR_MAX (NET_TCP_HDR_OPT_SIZE_MAX / NET_TCP_HDR_OPT_SIZE_WORD) #define NET_TCP_HDR_OPT_IX NET_TCP_HDR_SIZE_MIN /*$PAGE*/ /* ********************************************************************************************************* * TCP OPTION CONFIGURATION TYPE DEFINES * * Note(s) : (1) NET_TCP_OPT_CFG_TYPE_&&& #define values specifically chosen as ASCII representations of * the TCP option configuration types. Memory displays of TCP option configuration buffers * will display the TCP option configuration TYPEs with their chosen ASCII names. ********************************************************************************************************* */ /* ---------------- TCP OPT CFG TYPES ----------------- */ #if (CPU_CFG_ENDIAN_TYPE == CPU_ENDIAN_TYPE_BIG) #define NET_TCP_OPT_CFG_TYPE_NONE 0x4E4F4E45u /* "NONE" in ASCII. */ #define NET_TCP_OPT_CFG_TYPE_MAX_SEG_SIZE 0x4D535320u /* "MSS " in ASCII. */ #define NET_TCP_OPT_CFG_TYPE_WIN_SCALE 0x57494E20u /* "WIN " in ASCII (see 'net_tcp.h Note #1c1'). */ #define NET_TCP_OPT_CFG_TYPE_SACK_PERMIT 0x53434B50u /* "SCKP" in ASCII (see 'net_tcp.h Note #1c2'). */ #define NET_TCP_OPT_CFG_TYPE_SACK 0x5341434Bu /* "SACK" in ASCII (see 'net_tcp.h Note #1c2'). */ #define NET_TCP_OPT_CFG_TYPE_ECHO_REQ 0x45524551u /* "EREQ" in ASCII (see 'net_tcp.h Note #1c3'). */ #define NET_TCP_OPT_CFG_TYPE_ECHO_REPLY 0x4543484Fu /* "ECHO" in ASCII (see 'net_tcp.h Note #1c3'). */ #define NET_TCP_OPT_CFG_TYPE_TS 0x54532020u /* "TS " in ASCII (see 'net_tcp.h Note #1c4'). */ #else #if (CPU_CFG_DATA_SIZE == CPU_WORD_SIZE_32) #define NET_TCP_OPT_CFG_TYPE_NONE 0x454E4F4Eu /* "NONE" in ASCII. */ #define NET_TCP_OPT_CFG_TYPE_MAX_SEG_SIZE 0x2053534Du /* "MSS " in ASCII. */ #define NET_TCP_OPT_CFG_TYPE_WIN_SCALE 0x204E4957u /* "WIN " in ASCII (see 'net_tcp.h Note #1c1'). */ #define NET_TCP_OPT_CFG_TYPE_SACK_PERMIT 0x504B4353u /* "SCKP" in ASCII (see 'net_tcp.h Note #1c2'). */ #define NET_TCP_OPT_CFG_TYPE_SACK 0x4B434153u /* "SACK" in ASCII (see 'net_tcp.h Note #1c2'). */ #define NET_TCP_OPT_CFG_TYPE_ECHO_REQ 0x51455245u /* "EREQ" in ASCII (see 'net_tcp.h Note #1c3'). */ #define NET_TCP_OPT_CFG_TYPE_ECHO_REPLY 0x4F484345u /* "ECHO" in ASCII (see 'net_tcp.h Note #1c3'). */ #define NET_TCP_OPT_CFG_TYPE_TS 0x20205354u /* "TS " in ASCII (see 'net_tcp.h Note #1c4'). */ #elif (CPU_CFG_DATA_SIZE == CPU_WORD_SIZE_16) #define NET_TCP_OPT_CFG_TYPE_NONE 0x4F4E454Eu /* "NONE" in ASCII. */ #define NET_TCP_OPT_CFG_TYPE_MAX_SEG_SIZE 0x534D2053u /* "MSS " in ASCII. */ #define NET_TCP_OPT_CFG_TYPE_WIN_SCALE 0x4957204Eu /* "WIN " in ASCII (see 'net_tcp.h Note #1c1'). */ #define NET_TCP_OPT_CFG_TYPE_SACK_PERMIT 0x4353504Bu /* "SCKP" in ASCII (see 'net_tcp.h Note #1c2'). */ #define NET_TCP_OPT_CFG_TYPE_SACK 0x41534B43u /* "SACK" in ASCII (see 'net_tcp.h Note #1c2'). */ #define NET_TCP_OPT_CFG_TYPE_ECHO_REQ 0x52455145u /* "EREQ" in ASCII (see 'net_tcp.h Note #1c3'). */ #define NET_TCP_OPT_CFG_TYPE_ECHO_REPLY 0x43454F48u /* "ECHO" in ASCII (see 'net_tcp.h Note #1c3'). */ #define NET_TCP_OPT_CFG_TYPE_TS 0x53542020u /* "TS " in ASCII (see 'net_tcp.h Note #1c4'). */ #else /* Dflt CPU_WORD_SIZE_08. */ #define NET_TCP_OPT_CFG_TYPE_NONE 0x4E4F4E45u /* "NONE" in ASCII. */ #define NET_TCP_OPT_CFG_TYPE_MAX_SEG_SIZE 0x4D535320u /* "MSS " in ASCII. */ #define NET_TCP_OPT_CFG_TYPE_WIN_SCALE 0x57494E20u /* "WIN " in ASCII (see 'net_tcp.h Note #1c1'). */ #define NET_TCP_OPT_CFG_TYPE_SACK_PERMIT 0x53434B50u /* "SCKP" in ASCII (see 'net_tcp.h Note #1c2'). */ #define NET_TCP_OPT_CFG_TYPE_SACK 0x5341434Bu /* "SACK" in ASCII (see 'net_tcp.h Note #1c2'). */ #define NET_TCP_OPT_CFG_TYPE_ECHO_REQ 0x45524551u /* "EREQ" in ASCII (see 'net_tcp.h Note #1c3'). */ #define NET_TCP_OPT_CFG_TYPE_ECHO_REPLY 0x4543484Fu /* "ECHO" in ASCII (see 'net_tcp.h Note #1c3'). */ #define NET_TCP_OPT_CFG_TYPE_TS 0x54532020u /* "TS " in ASCII (see 'net_tcp.h Note #1c4'). */ #endif #endif /*$PAGE*/ /* ********************************************************************************************************* * TCP CONNECTION TIMEOUT DEFINES * * Note(s) : (1) (a) (1) RFC #1122, Section 4.2.2.13 'DISCUSSION' states that "the graceful close algorithm * of TCP requires that the connection state remain defined on (at least) one end of * the connection, for a timeout period of 2xMSL ... During this period, the (remote * socket, local socket) pair that defines the connection is busy and cannot be reused". * * (2) The following sections reiterate that the TIME-WAIT state timeout scalar is two * maximum segment lifetimes (2 MSL) : * * (A) RFC #793, Section 3.9 'Event Processing : SEGMENT ARRIVES : * Check Sequence Number : TIME-WAIT STATE' * (B) RFC #793, Section 3.9 'Event Processing : SEGMENT ARRIVES : * Check FIN Bit : TIME-WAIT STATE' * * (b) (1) RFC #793, Section 3.3 'Sequence Numbers : Knowing When to Keep Quiet' states that * "the Maximum Segment Lifetime (MSL) is ... to be 2 minutes. This is an engineering * choice, and may be changed if experience indicates it is desirable to do so". * * (2) Microsoft Corporation's Windows XP defaults MSL to 15 seconds. ********************************************************************************************************* */ /* Max seg timeout (see Note #1b) : */ #define NET_TCP_CONN_TIMEOUT_MAX_SEG_MIN_SEC ( 0u ) /* ... min = 0 seconds */ #define NET_TCP_CONN_TIMEOUT_MAX_SEG_MAX_SEC ( 2u * DEF_TIME_NBR_SEC_PER_MIN) /* ... max = 2 minutes */ #define NET_TCP_CONN_TIMEOUT_MAX_SEG_DFLT_SEC ( 15u ) /* ... dflt = 15 seconds */ #define NET_TCP_CONN_TIMEOUT_MAX_SEG_SCALAR 2u /* ... scalar (see Note #1a). */ #define NET_TCP_CONN_TIMEOUT_CONN_DFLT_SEC (120u * DEF_TIME_NBR_SEC_PER_MIN) /* Dflt conn timeout = 120 minutes */ #define NET_TCP_CONN_TIMEOUT_USER_DFLT_SEC ( 30u * DEF_TIME_NBR_SEC_PER_MIN) /* Dflt user timeout = 30 minutes */ /*$PAGE*/ /* ********************************************************************************************************* * TCP CONNECTION STATES * * Note(s) : (1) See the following RFC's for TCP state machine summary : * * (a) RFC # 793; Sections 3.2, 3.4, 3.5, 3.9 * (b) RFC #1122; Sections 4.2.2.8, 4.2.2.10, 4.2.2.11, 4.2.2.13, 4.2.2.18, 4.2.2.20 * * (2) (a) #### Additional closing-data-available state used for closing connections to allow the * application layer to receive any remaining data. * * See also 'net_tcp.c NetTCP_RxPktConnHandlerFinWait1() Note #2f5A2', * 'net_tcp.c NetTCP_RxPktConnHandlerFinWait2() Note #2f5B', * 'net_tcp.c NetTCP_RxPktConnHandlerClosing() Note #2d2B2a1B', * & 'net_tcp.c NetTCP_RxPktConnHandlerLastAck() Note #2d2A1b'. ********************************************************************************************************* */ #define NET_TCP_CONN_STATE_NONE 0u #define NET_TCP_CONN_STATE_FREE 1u #define NET_TCP_CONN_STATE_CLOSED 10u #define NET_TCP_CONN_STATE_LISTEN 20u #define NET_TCP_CONN_STATE_SYNC_RXD 30u #define NET_TCP_CONN_STATE_SYNC_RXD_PASSIVE 31u #define NET_TCP_CONN_STATE_SYNC_RXD_ACTIVE 32u #define NET_TCP_CONN_STATE_SYNC_TXD 35u #define NET_TCP_CONN_STATE_CONN 40u #define NET_TCP_CONN_STATE_FIN_WAIT_1 50u #define NET_TCP_CONN_STATE_FIN_WAIT_2 51u #define NET_TCP_CONN_STATE_CLOSING 52u #define NET_TCP_CONN_STATE_TIME_WAIT 53u #define NET_TCP_CONN_STATE_CLOSE_WAIT 55u #define NET_TCP_CONN_STATE_LAST_ACK 56u #define NET_TCP_CONN_STATE_CLOSING_DATA_AVAIL 59u /* See Note #2a. */ /* ********************************************************************************************************* * TCP CONNECTION QUEUE STATES ********************************************************************************************************* */ #define NET_TCP_RX_Q_STATE_NONE 0u #define NET_TCP_RX_Q_STATE_CLOSED 100u #define NET_TCP_RX_Q_STATE_CLOSING 101u #define NET_TCP_RX_Q_STATE_SYNC 110u #define NET_TCP_RX_Q_STATE_CONN 111u #define NET_TCP_TX_Q_STATE_NONE 0u #define NET_TCP_TX_Q_STATE_CLOSED 200u #define NET_TCP_TX_Q_STATE_CLOSING 201u #define NET_TCP_TX_Q_STATE_SYNC 210u #define NET_TCP_TX_Q_STATE_CONN 211u #define NET_TCP_TX_Q_STATE_SUSPEND 215u #define NET_TCP_TX_Q_STATE_CLOSED_SUSPEND 220u #define NET_TCP_TX_Q_STATE_CLOSING_SUSPEND 221u /*$PAGE*/ /* ********************************************************************************************************* * TCP CONNECTION CODE DEFINES **************
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上传用户：the same kong
1. 日语假名及其发音一览 平 片 罗 平 片 罗 平 片 罗 平 片 罗 平 片 罗 假 假 马 假 假 马 假 假 马 假 假 马 假 假 马 音 音 音 音 音 ______________________________________________________________________________ あ ア a い イ i う ウ u え エ e お オ o か カ ka き キ ki く ク ku け ケ ke こ コ ko さ サ sa し シ si/shi す ス su せ セ se そ ソ so た タ ta ち チ chi つ ツ tsu て テ te と ト to な ナ na に ニ ni ぬ ヌ nu ね ネ ne の ノ no は ハ ha ひ ヒ hi ふ フ fu へ ヘ he ほ ホ ho ま マ ma み ミ mi む ム mu め メ me も モ mo や ヤ ya ゆ ユ yu よ ヨ yo ら ラ ra り リ ri る ル ru れ レ re ろ ロ ro わ ワ wa を ヲ o/wo ん ン n が ガ ga ぎ ギ gi ぐ グ gu げ ゲ ge ご ゴ go ざ ザ za じ ジ zi/ji ず ズ zu ぜ ゼ ze ぞ ゾ zo だ ダ da ぢ ヂ ji/di づ ヅ zu/du で デ de ど ド do ば バ ba び ビ bi ぶ ブ bu べ ベ be ぼ ボ bo ぱ パ pa ぴ ピ pi ぷ プ pu ぺ ペ pe ぽ ポ po きゃ キャ kya きゅ キュ kyu きょ キョ kyo しゃ シャ sya しゅ シュ syu しょ ショ syo ちゃ チャ cya ちゅ チュ cyu ちょ チョ cyo にゃ ニャ nya にゅ ニュ nyu にょ ニョ nyo ひゃ ヒャ hya ひゅ ヒュ hyu ひょ ヒョ hyo みゃ ミャ mya みゅ ミュ myu みょ ミョ myo りゃ リャ rya りゅ リュ ryu りょ リョ ryo ぎゃ ギャ gya ぎゅ ギュ gyu ぎょ ギョ gyo じゃ ジャ zya/ja じゅ ジュ yu/ju じょ ジョzyo/jo びゃ ビャ bya びゅ ビュ byu びょ ビョ byo ぴゃ ピャ pya ぴゅ ピュ pyu ぴょ ピョ pyo
标签： 日语
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上传用户：sxc1997
This book is an entry-level text on the technology of telecommunications. It has been crafted with the newcomer in mind. The eighteen chapters of text have been prepared for high-school graduates who understand algebra, logarithms, and basic electrical prin- ciples such as Ohm’s law. However, many users require support in these areas so Appen- dices A and B review the essentials of electricity and mathematics through logarithms.
标签： Telecommunications Fundamentals 1st of ed
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上传用户：shancjb
This book is an entry-level text on the technology of telecommunications. It has been crafted with the newcomer in mind. The twenty-one chapters of text have been prepared for high-school graduates who understand algebra, logarithms, and the basic principles of electricity such as Ohm’s law. However, it is appreciated that many readers require support in these areas. Appendices A and B review the essentials of electricity and mathematics up through logarithms. This material was placed in the appendices so as not to distract from the main theme, the technology of telecommunication systems. Another topic that many in the industry find difficult is the use of decibels and derived units. Appendix C provides the reader a basic understanding of decibels and their applications. The only mathematics necessary is an understanding of the powers of ten
标签： Telecommunications Fundamentals 2nd of ed
上传时间： 2020-05-27
上传用户：shancjb
