<>前天夜晚忙到半夜,作了一根gps到pda的转换线。专用接口到串口。</P>
<><img src="attachments/dvbbs/2004-5/200451021324744.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor=\'hand\'; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onclick="if(!this.resized) {return true;} else {window.open(\'attachments/dvbbs/2004-5/200451021324744.jpg\');}" onmousewheel="return imgzoom(this);" alt="" />
别看是串口线,但因为pda输出的是ttl电平,所以需要在中间有电平转换电路。用max232和4颗电容搞定。最难的是pda的借口定义找不到,没有示波器,只能根据电路板判断和试验,最终找出了TTL的in和out端口。</P><img src="attachments/dvbbs/2004-5/200451021627755.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor=\'hand\'; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onclick="if(!this.resized) {return true;} else {window.open(\'attachments/dvbbs/2004-5/200451021627755.jpg\');}" onmousewheel="return imgzoom(this);" alt="" />
<>电子市场找不到零买小型电容的,wjh啥时候帮我找几个阿,10uf到1uf的就行,那种很细的电解电容。</P><img src="attachments/dvbbs/2004-5/200451021845964.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor=\'hand\'; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onclick="if(!this.resized) {return true;} else {window.open(\'attachments/dvbbs/2004-5/200451021845964.jpg\');}" onmousewheel="return imgzoom(this);" alt="" />
呵呵,gps+pda
<>装上车,把长长的连接线固定好。下次再作个短的,专门连gps和pda用。</P><img src="attachments/dvbbs/2004-5/2004510211119809.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor=\'hand\'; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onclick="if(!this.resized) {return true;} else {window.open(\'attachments/dvbbs/2004-5/2004510211119809.jpg\');}" onmousewheel="return imgzoom(this);" alt="" />
<img src="attachments/dvbbs/2004-5/2004510211257585.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor=\'hand\'; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onclick="if(!this.resized) {return true;} else {window.open(\'attachments/dvbbs/2004-5/2004510211257585.jpg\');}" onmousewheel="return imgzoom(this);" alt="" />
<><img src="attachments/dvbbs/2004-5/2004510211426170.jpg" border="0" onload="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onmouseover="if(this.width>screen.width*0.7) {this.resized=true; this.width=screen.width*0.7; this.style.cursor=\'hand\'; this.alt=\'Click here to open new window\nCTRL+Mouse wheel to zoom in/out\';}" onclick="if(!this.resized) {return true;} else {window.open(\'attachments/dvbbs/2004-5/2004510211426170.jpg\');}" onmousewheel="return imgzoom(this);" alt="" />
到钱塘江边了。可以看见箭头的方向。就是我的前进方向。</P>
<>速度是8.7。因为gps对速度的反应有点迟钝,他需要3-4秒来计算当前速度。所以显示不一样,只有 7.22.</P>
<>右边gps显示卫星图,现在收到6颗卫星的信号,精确度6米</P>