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<div id="pf1" class="pf w0 h0" data-page-no="1"><div class="pc pc1 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/62550d42b744eb386fd7d5f8/bg1.jpg"><div class="c x0 y1 w0 h2"><div class="t m0 x1 h3 y2 ff1 fs0 fc0 sc0 ls0 ws0">Multi-function watt-hour meter communication protocol DL/T 645-1997</div><div class="t m0 x2 h3 y3 ff1 fs0 fc0 sc0 ls0 ws0">1. Range</div><div class="t m0 x2 h3 y4 ff1 fs0 fc0 sc0 ls0 ws0">The standardization is used for the tariff device of multi-function watt-hour meter to do point to </div><div class="t m0 x2 h3 y5 ff1 fs0 fc0 sc0 ls0 ws0">point or one master to multi-slaves data exchange with hand-held unit(HHU) or other data ter<span class="_ _0"></span>minal </div><div class="t m0 x2 h3 y6 ff1 fs0 fc0 sc0 ls0 ws0">equipments. It defines the technical specification of ph<span class="_ _0"></span>ysical connection, communication link and </div><div class="t m0 x2 h3 y7 ff1 fs0 fc0 sc0 ls0 ws0">application.</div><div class="t m0 x2 h3 y8 ff1 fs0 fc0 sc0 ls0 ws0">4 Physical layer</div><div class="t m0 x2 h3 y9 ff1 fs0 fc0 sc0 ls0 ws0">………………………………………………….</div><div class="t m0 x2 h3 ya ff1 fs0 fc0 sc0 ls0 ws0">4.1.6 Electrical characteristics of reading head</div><div class="t m0 x3 h3 yb ff1 fs0 fc0 sc0 ls0 ws0">The reading head should be able to do data exchange with data terminal equipment.<span class="_ _0"></span> Its </div><div class="t m0 x3 h3 yc ff1 fs0 fc0 sc0 ls0 ws0">communication interface is TTL<span class="_ _1"></span> level, or according to ITU-TV<span class="_ _2"></span>.24 and ITU-TV<span class="_ _2"></span>.28. <span class="_ _1"></span>The </div><div class="t m0 x3 h3 yd ff1 fs0 fc0 sc0 ls0 ws0">electrical characteristics of reading head are<span class="_ _0"></span> shown in fig.4.</div><div class="t m0 x2 h3 ye ff1 fs0 fc0 sc0 ls0 ws0">4.1.6.1 W<span class="_ _3"></span>orking limit of reading head</div><div class="t m0 x3 h3 yf ff1 fs0 fc0 sc0 ls0 ws0">Signal level </div><div class="t m0 x3 h3 y10 ff1 fs0 fc0 sc0 ls0 ws0"> </div><div class="t m0 x4 h3 y11 ff1 fs0 fc0 sc0 ls0 ws0"> OFF status <span class="_ _4"> </span>ON status</div><div class="t m0 x4 h3 y12 ff1 fs0 fc0 sc0 ls0 ws0">Binary “1”<span class="_ _5"> </span>Binary “0”</div><div class="t m0 x4 h3 y13 ff1 fs0 fc0 sc0 ls0 ws0">MARK<span class="_ _6"> </span>SP<span class="_ _3"></span>ACE</div><div class="t m0 x4 h3 y14 ff1 fs0 fc0 sc0 ls0 ws0">Switch off li<span class="_ _1"></span>ght<span class="_ _0"></span> source<span class="_ _7"> </span>Switch on light source</div><div class="t m0 x4 h3 y15 ff1 fs0 fc0 sc0 ls0 ws0"><-3V(V<span class="_ _2"></span>.28)<span class="_ _8"> </span>>+3V(V<span class="_ _2"></span>.28)</div><div class="t m0 x4 h3 y16 ff1 fs0 fc0 sc0 ls0 ws0"><=0.8V(TTL<span class="_ _1"></span> input)<span class="_ _9"> </span>>=2V(TTL<span class="_ _1"></span> input)</div><div class="t m0 x4 h3 y17 ff1 fs0 fc0 sc0 ls0 ws0">-0.5V~0.4V(TTL<span class="_ _1"></span> output)<span class="_ _a"> </span>2.4V~Up(TTL<span class="_ _1"></span> output)</div><div class="t m0 x3 h3 y18 ff1 fs0 fc0 sc0 ls0 ws0">Note: TTL<span class="_ _1"></span> negative logic is used here.</div><div class="t m0 x2 h3 y19 ff1 fs0 fc0 sc0 ls0 ws0">4.1.6.2 T<span class="_ _1"></span>ransfer speed</div><div class="t m0 x5 h3 y1a ff1 fs0 fc0 sc0 ls0 ws0">Max transfer speed should be no lower than 2400bps.</div><div class="t m0 x2 h3 y1b ff1 fs0 fc0 sc0 ls0 ws0">4.1.7 Power supply for working</div><div class="t m0 x5 h3 y1c ff1 fs0 fc0 sc0 ls0 ws0">The power supply of reading head is provided by hand-held unit or other data<span class="_ _0"></span> terminal </div><div class="t m0 x5 h3 y1d ff1 fs0 fc0 sc0 ls0 ws0">equipment connected with it.</div></div><div class="t m0 x5 h3 y1e ff1 fs0 fc0 sc0 ls0 ws0">a)</div><div class="t m0 x6 h3 y1f ff1 fs0 fc0 sc0 ls0 ws0"> 0 1 0 1</div><div class="t m0 x5 h3 y20 ff1 fs0 fc0 sc0 ls0 ws0">(b)</div><div class="t m0 x7 h3 y21 ff1 fs0 fc0 sc0 ls0 ws0"> </div><div class="c x8 y21 w2 h4"><div class="t m1 x0 h5 y22 ff1 fs1 fc0 sc0 ls0 ws0"><span class="fc1 sc0"> </span></div></div><div class="t m0 x5 h3 y23 ff1 fs0 fc0 sc0 ls0 ws0"> ON 0 1 0 1</div><div class="t m0 x9 h3 y24 ff1 fs0 fc0 sc0 ls0 ws0">Fig.5 signal and modulation</div><div class="t m0 x5 h3 y25 ff1 fs0 fc0 sc0 ls0 ws0">a)<span class="_ _b"> </span>electrical signal with no modulation b)infrared light signal after<span class="_ _0"></span> modulation</div><div class="c x0 y1 w0 h2"><div class="t m0 xa h3 y26 ff1 fs0 fc0 sc0 ls0 ws0">Fig.6 angle of light radiation</div></div><div class="t m0 xb h6 y27 ff2 fs1 fc0 sc0 ls0 ws0">OFF</div><div class="t m0 xc h7 y28 ff3 fs0 fc0 sc0 ls0 ws0">θ</div></div><div class="pi" data-data='{"ctm":[1.611639,0.000000,0.000000,1.611639,0.000000,0.000000]}'></div></div>
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<div id="pf2" class="pf w0 h0" data-page-no="2"><div class="pc pc2 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/62550d42b744eb386fd7d5f8/bg2.jpg"><div class="c x0 y1 w0 h2"><div class="t m0 x2 h3 y2 ff1 fs0 fc0 sc0 ls0 ws0">4.2 Infrared light interface of modulation t<span class="_ _0"></span>y<span class="_ _1"></span>p<span class="_ _0"></span>e</div><div class="t m0 x2 h3 y29 ff1 fs0 fc0 sc0 ls0 ws0">4.2.1 Modulation characteristics</div><div class="t m0 x5 h3 y3 ff1 fs0 fc0 sc0 ls0 ws0">The modulation of the signal is as Fig.5. The carrier frequency is 38kHz±1kHz</div><div class="t m0 x2 h3 y4 ff1 fs0 fc0 sc0 ls0 ws0">4.2.2 Optical characteristics</div><div class="t m0 x2 h8 y5 ff1 fs0 fc0 sc0 ls0 ws0">4.2.2.1 Reference temperature 23<span class="_ _c"> </span>±2<span class="_ _d"></span><span class="ff4">℃<span class="_ _c"> </span>℃</span></div><div class="t m0 x2 h7 y2a ff1 fs0 fc0 sc0 ls0 ws0">4.2.2.2 Half-angle of light radiation <span class="ff3">θ</span></div><div class="t m0 x5 h7 y2b ff3 fs0 fc0 sc0 ls0 ws0">θ<span class="ff1"> </span>≥<span class="ff1">15</span>°<span class="ff1"> (as Fig.6) </span></div><div class="t m0 x2 h3 y2c ff1 fs0 fc0 sc0 ls0 ws0">4.2.2.3 W<span class="_ _3"></span>ave length</div><div class="t m0 x5 h3 y2d ff1 fs0 fc0 sc0 ls0 ws0"> The wave length of infrared light is 900nm~1000nm</div><div class="t m0 x2 h3 y2e ff1 fs0 fc0 sc0 ls0 ws0">4.2.2.4 Emitter</div><div class="t m0 x5 h3 y2f ff1 fs0 fc0 sc0 ls0 ws0">The emitter produces infrared light with irradiance <span class="_ _0"></span><span class="ff5">E</span></div><div class="t m0 xd h9 y30 ff1 fs2 fc0 sc0 ls0 ws0">e/r</div><div class="t m0 xe h7 y2f ff1 fs0 fc0 sc0 ls0 ws0"> <span class="ff3">≥</span>50mW/m</div><div class="t m0 xf h9 yb ff1 fs2 fc0 sc0 ls0 ws0">2</div><div class="t m0 x10 h3 y2f ff1 fs0 fc0 sc0 ls0 ws0"> on the light axis 1m </div><div class="t m0 x5 h3 y31 ff1 fs0 fc0 sc0 ls0 ws0">away from the surface of emitter </div><div class="t m0 x2 h3 y32 ff1 fs0 fc0 sc0 ls0 ws0">4.2.2.5 Receiver</div><div class="t m0 x5 h3 y33 ff1 fs0 fc0 sc0 ls0 ws0">The irradiance <span class="ff5">E</span></div><div class="t m0 x11 h9 y34 ff1 fs2 fc0 sc0 ls0 ws0">e/r</div><div class="t m0 x12 h3 y33 ff1 fs0 fc0 sc0 ls0 ws0"> of the receiver on the light axis 10mm away from the surface of receiver<span class="_ _0"></span> </div><div class="t m0 x5 h3 y35 ff1 fs0 fc0 sc0 ls0 ws0">should satisfy following conditions:</div><div class="t m0 x13 h3 y36 ff1 fs0 fc0 sc0 ls0 ws0">Irradiance of infrared light<span class="_ _e"> </span>Status of receiver</div><div class="t m0 x13 h3 y37 ff1 fs0 fc0 sc0 ls0 ws0">0.35mW/m</div><div class="t m0 x14 h9 y11 ff1 fs2 fc0 sc0 ls0 ws0">2</div><div class="t m0 x15 h7 y37 ff3 fs0 fc0 sc0 ls0 ws0">≤<span class="ff5">E</span></div><div class="t m0 x16 h9 y38 ff1 fs2 fc0 sc0 ls0 ws0">e/r</div><div class="t m0 x17 h7 y37 ff1 fs0 fc0 sc0 ls0 ws0"> <span class="ff3">≤</span>20000mW/m</div><div class="t m0 x18 h9 y11 ff1 fs2 fc0 sc0 ls0 ws0">2</div><div class="t m0 x19 h3 y39 ff1 fs0 fc0 sc0 ls0 ws0">ON</div><div class="t m0 x13 ha y3a ff5 fs0 fc0 sc0 ls0 ws0">E</div><div class="t m0 x1a h9 y3b ff1 fs2 fc0 sc0 ls0 ws0">e/r</div><div class="t m0 x1b h7 y3a ff1 fs0 fc0 sc0 ls0 ws0"> <span class="ff3">≤0.2</span>mW/m</div><div class="t m0 x7 h9 y3c ff1 fs2 fc0 sc0 ls0 ws0">2</div><div class="t m0 x19 h3 y3d ff1 fs0 fc0 sc0 ls0 ws0">OFF</div><div class="t m0 x2 h3 y3e ff1 fs0 fc0 sc0 ls0 ws0">4.2.2.6 Environment condition of the light</div><div class="t m0 x5 h3 y3f ff1 fs0 fc0 sc0 ls0 ws0">According to 4.1.5.4, the valid distance of communication is longer than 4<span class="_ _0"></span>m under the </div><div class="t m0 x5 h3 y40 ff1 fs0 fc0 sc0 ls0 ws0">environment.</div><div class="t m0 x2 h3 y41 ff1 fs0 fc0 sc0 ls0 ws0">4.2.3 Electrical characteristics</div><div class="t m0 x5 h3 y42 ff1 fs0 fc0 sc0 ls0 ws0">It's according to 4.1.6, but transfer speed should be no higher than 1200bps.</div><div class="t m0 x2 h3 y43 ff1 fs0 fc0 sc0 ls0 ws0">4.2.4 Use condition</div><div class="t m0 x2 h3 y44 ff1 fs0 fc0 sc0 ls0 ws0">4.2.4.1 It's should be avoided that strong light (sunlight and fluorescent light) directly irradiate the<span class="_ _0"></span> </div><div class="t m0 x2 h3 y45 ff1 fs0 fc0 sc0 ls0 ws0">receiving window of infrared light receiver<span class="_ _1"></span>.</div><div class="t m0 x2 h3 y46 ff1 fs0 fc0 sc0 ls0 ws0">4.2.4.2 It should be tried to keep the optical axis of the receiver consistent w<span class="_ _0"></span>ith that of the emitter </div><div class="t m0 x2 h3 y47 ff1 fs0 fc0 sc0 ls0 ws0">when working.</div><div class="t m0 x2 h3 y48 ff1 fs0 fc0 sc0 ls0 ws0">4.2.4.3 <span class="_ _1"></span>A<span class="_ _3"></span>void of appearing<span class="_ _0"></span> multiple consecutive“0” in the data.</div><div class="t m0 x2 h3 y49 ff1 fs0 fc0 sc0 ls0 ws0">4.3 Electrical interface of serial port RS-485</div><div class="t m0 x2 h3 y4a ff1 fs0 fc0 sc0 ls0 ws0"> RS-485 is used by the standardization which make it's possible for multi-points connection. The </div><div class="t m0 x2 h3 y4b ff1 fs0 fc0 sc0 ls0 ws0">general performance of RS-485 interface should accord with following specification.</div><div class="t m0 x2 h7 y4c ff1 fs0 fc0 sc0 ls0 ws0">4.3.1 Electrostatic discharge (ESD) resistance of driver and receiver side is <span class="ff3">±</span>15V (human-bod<span class="_ _0"></span>y </div><div class="t m0 x2 h3 y4d ff1 fs0 fc0 sc0 ls0 ws0">model)</div><div class="t m0 x2 h3 y4e ff1 fs0 fc0 sc0 ls0 ws0">4.3.2 Common mode input voltage: -7V~+12V<span class="_ _2"></span>.</div><div class="t m0 x2 h3 y4f ff1 fs0 fc0 sc0 ls0 ws0">4.3.3 Differential m<span class="_ _f"></span>ode input voltage: upper than 0.2V</div><div class="t m0 x2 h3 y50 ff1 fs0 fc0 sc0 ls0 ws0">4.3.4 Output voltage of driver: When the impedance of load is 54, the max output voltage of </div><div class="t m0 x2 h3 y51 ff1 fs0 fc0 sc0 ls0 ws0">driver is 5V and the min is 1.5V<span class="_ _2"></span>.</div><div class="t m0 x2 h3 y52 ff1 fs0 fc0 sc0 ls0 ws0">4.3.5 T<span class="_ _1"></span>ri-state output</div><div class="t m0 x2 h3 y53 ff1 fs0 fc0 sc0 ls0 ws0">4.3.6 Half-duplex communication mode</div><div class="t m0 x2 h3 y54 ff1 fs0 fc0 sc0 ls0 ws0">4.3.7 The driven capability should be no less than 32 interfaces of the same type </div><div class="t m0 x2 h3 y55 ff1 fs0 fc0 sc0 ls0 ws0">4.3.8 The valid distance of transfer should be no less than 1200m when the transfer speed is no </div><div class="t m0 x2 h3 y56 ff1 fs0 fc0 sc0 ls0 ws0">higher than 100kbps.</div><div class="t m0 x2 h3 y57 ff1 fs0 fc0 sc0 ls0 ws0">4.3.9 The bu<span class="_ _f"></span>s is passive power<span class="_ _1"></span>. <span class="_ _1"></span>The tar<span class="_ _0"></span>if<span class="_ _f"></span>f device or data terminal equipment provide isolation </div><div class="t m0 x2 h3 y58 ff1 fs0 fc0 sc0 ls0 ws0">power for it.</div></div></div><div class="pi" data-data='{"ctm":[1.611639,0.000000,0.000000,1.611639,0.000000,0.000000]}'></div></div>
<div id="pf3" class="pf w0 h0" data-page-no="3"><div class="pc pc3 w0 h0"><img class="bi x0 y0 w1 h1" alt="" src="https://static.pudn.com/prod/directory_preview_static/62550d42b744eb386fd7d5f8/bg3.jpg"><div class="c x0 y1 w0 h2"><div class="t m0 x2 h3 y29 ff1 fs0 fc0 sc0 ls0 ws0">5 Data-link layer</div><div class="t m0 x5 h3 y3 ff1 fs0 fc0 sc0 ls0 ws0">The protocol uses communication mode of master-slave structure and half-duplex. <span class="_ _1"></span>The </div><div class="t m0 x2 h3 y4 ff1 fs0 fc0 sc0 ls0 ws0">hand-held unit or other data terminal is master station and tariff device is salve station. Each tariff </div><div class="t m0 x2 h3 y5 ff1 fs0 fc0 sc0 ls0 ws0">device has its own address code. The creation and release of communication link is controlled by </div><div class="t m0 x2 h3 y6 ff1 fs0 fc0 sc0 ls0 ws0">the master station sending information frame. Each frame is composed of 7 parts including start<span class="_ _0"></span> </div><div class="t m0 x2 h3 y7 ff1 fs0 fc0 sc0 ls0 ws0">flag, address field of slave station, control code, data length, data field, check<span class="_ _0"></span> code of frame and end </div><div class="t m0 x2 h3 y8 ff1 fs0 fc0 sc0 ls0 ws0">flag, in which each part is composed of several b<span class="_ _0"></span>y<span class="_ _1"></span>t<span class="_ _0"></span>es.</div><div class="t m0 x2 h3 y9 ff1 fs0 fc0 sc0 ls0 ws0">5.1 Byte format</div></div><div class="c x3 y59 w3 hb"><div class="t m2 x0 hc y5a ff1 fs3 fc0 sc0 ls0 ws0"> </div></div><div class="c x1c y5b w4 hd"><div class="t m3 x1d he y5c ff1 fs4 fc0 sc0 ls0 ws0">D2 </div></div><div class="c x1e y5b w4 hd"><div class="t m3 x1d he y5c ff1 fs4 fc0 sc0 ls0 ws0">D3 </div></div><div class="c x1f y5b w4 hd"><div class="t m3 x1d he y5c ff1 fs4 fc0 sc0 ls0 ws0">D4 </div></div><div class="c x20 y5b w4 hd"><div class="t m3 x1d he y5c ff1 fs4 fc0 sc0 ls0 ws0">D5 </div></div><div class="c x21 y5b w4 hd"><div class="t m3 x1d he y5c ff1 fs4 fc0 sc0 ls0 ws0">D6 </div></div><div class="c x22 y5b w4 hd"><div class="t m3 x1d he y5c ff1 fs4 fc0 sc0 ls0 ws0">D7 </div></div><div class="c x23 y5b w4 hd"><div class="t m3 x1d he y5c ff1 fs4 fc0 sc0 ls0 ws0">P </div></div><div class="c x24 y5b w4 hd"><div class="t m3 x1d he y5c ff1 fs4 fc0 sc0 ls0 ws0">1 </div></div><div class="c x25 y5d w4 hf"><div class="t m3 x1d he y5e ff1 fs4 fc0 sc0 ls0 ws0">D1 </div></div><div class="c x26 y5d w4 hf"><div class="t m3 x1d he y5e ff1 fs4 fc0 sc0 ls0 ws0">D0 </div></div><div class="c x27 y5d w4 hf"><div class="t m3 x1d he y5e ff1 fs4 fc0 sc0 ls0 ws0">0 </div></div><div class="c x3 y5f w5 h10"><div class="t m2 x1d hc y60 ff1 fs3 fc0 sc0 ls0 ws0">T<span class="_ _1"></span>ransfer <span class="_ _10"> </span>directi<span class="_ _1"></span>o<span class="_ _0"></span>n </div><div class="t m2 x1d hc y61 ff1 fs3 fc0 sc0 ls0 ws0"><span class="fc1 sc0">d</span><span class="fc1 sc0">D</span><span class="fc1 sc0">v</span><span class="fc1 sc0">d</span><span class="fc1 sc0">i</span><span class="fc1 sc0">r</span><span class="fc1 sc0">e</span><span class="fc1 sc0">c</span><span class="fc1 sc0">t</span><span class="fc1 sc0">i</span><span class="_ _1"></span><span class="fc1 sc0">o</span><span class="fc1 sc0">n</span><span class="_ _0"></span><span class="fc1 sc0"> </span></div></div><div class="c x16 y62 w6 h10"><div class="t m2 x1d hc y63 ff1 fs3 fc0 sc0 ls0 ws0">S<span class="_ _1"></span>tart bit </div></div><div class="c x1c y62 w7 h10"><div class="t m2 x1d hc y63 ff1 fs3 fc0 sc0 ls0 ws0">Data of 8<span class="_ _1"></span> bits </div></div><div class="c x28 y62 w7 h10"><div class="t m2 x1d hc y63 ff1 fs3 fc0 sc0 ls0 ws0">Even ch<span class="_ _1"></span>eck bit </div></div><div class="c x29 y62 w8 h10"><div class="t m2 x1d hc y63 ff1 fs3 fc0 sc0 ls0 ws0">S<span class="_ _1"></span>top bit </div></div><div class="t m0 x2a h3 y64 ff1 fs0 fc0 sc0 ls0 ws0">Fig.7 transfer sequence of byte</div><div class="c x0 y1 w0 h2"><div class="t m0 x4 h3 y65 ff1 fs0 fc0 sc0 ls0 ws0">Instruction<span class="_ _11"> </span>Code</div><div class="t m0 x4 h3 y66 ff1 fs0 fc0 sc0 ls0 ws0">Frame start flag<span class="_ _12"> </span>68H</div><div class="t m0 x4 h3 y67 ff1 fs0 fc0 sc0 ls0 ws0">Address field<span class="_ _13"> </span>A0</div><div class="t m0 x2b h3 y68 ff1 fs0 fc0 sc0 ls0 ws0">A1</div><div class="t m0 x2b h3 y19 ff1 fs0 fc0 sc0 ls0 ws0">A2</div><div class="t m0 x2b h3 y69 ff1 fs0 fc0 sc0 ls0 ws0">A3</div><div class="t m0 x2b h3 y6a ff1 fs0 fc0 sc0 ls0 ws0">A4</div><div class="t m0 x2b h3 y6b ff1 fs0 fc0 sc0 ls0 ws0">A5</div><div class="t m0 x4 h3 y6c ff1 fs0 fc0 sc0 ls0 ws0">Frame start flag<span class="_ _12"> </span>68h</div><div class="t m0 x4 h3 y6d ff1 fs0 fc0 sc0 ls0 ws0">Control code<span class="_ _14"> </span>C</div><div class="t m0 x4 h3 y6e ff1 fs0 fc0 sc0 ls0 ws0">Data length<span class="_ _8"> </span>L</div><div class="t m0 x4 h3 y6f ff1 fs0 fc0 sc0 ls0 ws0">Data<span class="_ _15"> </span>DA<span class="_ _2"></span>T<span class="_ _16"></span>A</div><div class="t m0 x4 h3 y70 ff1 fs0 fc0 sc0 ls0 ws0">Check code<span class="_ _17"> </span>CS</div><div class="t m0 x4 h3 y71 ff1 fs0 fc0 sc0 ls0 ws0">End flag<span class="_ _18"> </span>16H</div><div class="t m0 x2c h3 y72 ff1 fs0 fc0 sc0 ls0 ws0">Fig.8 Frame format</div><div class="t m0 x3 h3 y73 ff1 fs0 fc0 sc0 ls0 ws0">Each byte has 8 bits binary code. <span class="_ _1"></span>A<span class="_ _16"></span> start bi t<span class="_ _0"></span> (0), an even check bit and a stop bit are added when </div><div class="t m0 x3 h3 y74 ff1 fs0 fc0 sc0 ls0 ws0">transferring. So the total is 1<span class="_ _1"></span>1 bits. The sequence of transfer is as Fig.7. <span class="_ _f"></span>The D0 is the LSB (least<span class="_ _0"></span> </div><div class="t m0 x3 h3 y75 ff1 fs0 fc0 sc0 ls0 ws0">significant bit) and D7 is the MSB (most significant bit). The transfer order is that the bit in </div><div class="t m0 x3 h3 y76 ff1 fs0 fc0 sc0 ls0 ws0">lower address is transferred first and then the bit in higher address.</div><div class="t m0 x2 h3 y77 ff1 fs0 fc0 sc0 ls0 ws0">5.2 Frame format</div><div class="t m0 x3 h3 y78 ff1 fs0 fc0 sc0 ls0 ws0">The frame is the basic unit for transferring information. The frame format is shown in fig.8.</div></div></div><div class="pi" data-data='{"ctm":[1.611639,0.000000,0.000000,1.611639,0.000000,0.000000]}'></div></div>
