中心议题:
* stm8s103 + TM1812做的自行车轮POV
实物图如下,设计很不完善,很多失误,所以板子做出来一方面尺寸有问题,另外飞了N条线。
下面这个是应该达到的效果
下面这个是原理图:
用stm8s的高速IO的时候一定要注意上拉。
下面这个是取模软件:
风火轮全彩取模0.1版
http://www.52solution.com/data/datainfo/id/6154
下面是一个取模的范例:
% test_led_wheel
% for your reference
ri = 0.1;
div_p = 128;
% div_p = 256;
div_r = 24;
% div_r = 36;
bit = 4;
% read RGB from img
img_w = size(img, 2);
img_h = size(img, 1);
img_cx = round(img_w / 2 - 1);
img_cy = round(img_h / 2 - 1);
img_r = min(img_cx, img_cy);
figure;
hold on;
axis equal;
whitebg('k');
xlim([-1.1, 1.1]);
ylim([-1.1, 1.1]);
for i=1:div_p
% plot([ri*cos(2*pi*i/div_p), cos(2*pi*i/div_p)], ...
% [ri*sin(2*pi*i/div_p), sin(2*pi*i/div_p)]);
for j=1:div_r
pr = ((1-ri)/(div_r-1)*(j-1)+ri);
px1 = cos(2*pi*(i-1)/div_p);
px2 = cos(2*pi*(i)/div_p);
py1 = sin(2*pi*(i-1)/div_p);
py2 = sin(2*pi*(i)/div_p);
% pc = [i/div_p,j/div_r,(2-i/div_p-j/div_r)/2];
ix = min(round(img_cx + img_r*px1*pr)+1, img_w);
iy = min(round(img_cy + img_r*py1*pr)+1, img_h);
icr = img(iy, ix, 1);
icg = img(iy, ix, 2);
icb = img(iy, ix, 3);
pc = single([icr, icg, icb]/2^(8-bit)) * 2^(8-bit) / 256;
plot( pr * px1, -pr * py1, '.', ...
'MarkerEdgeColor', pc );
end;
end;
% byte = div_r * div_p * bit / 8
% dw = 0.7; % m
% v = 40; % km/h
% n = v/3.6/dw/pi % rps
% dt = 1/n/div_p * 1000 % ms
效果图:
程序解读:
运行程序之前,需要先用matlab导入一张图像,将其点阵数据保存成变量img。
导入可以用imtool命令打开图像工具箱然后导入,也可以在matlab主菜单中import data那里
开头,
ri = 0.1;
指定环内径比例(按外径ro=1,比如外径330mm那么内径330×0.1=33mm)
div_p = 128;
是设定自行车轮转一周要刷新的次数,或者说圆周分辨率。
div_r = 24;
是半径上面布置的LED数量。或者说半径分辨率。
bit = 4;
是每个点的数据位数。bit有效取值:1~8
img_w = size(img, 2);
img_h = size(img, 1);
img_cx = round(img_w / 2 - 1);
img_cy = round(img_h / 2 - 1);
img_r = min(img_cx, img_cy);
获得图像的宽、高、中心坐标、有效半径
两个循环里面,
pr = ((1-ri)/(div_r-1)*(j-1)+ri);
px1 = cos(2*pi*(i-1)/div_p);
px2 = cos(2*pi*(i)/div_p);
py1 = sin(2*pi*(i-1)/div_p);
py2 = sin(2*pi*(i)/div_p);
将圆坐标转换成平面直角坐标
ix = min(round(img_cx + img_r*px1*pr)+1, img_w);
iy = min(round(img_cy + img_r*py1*pr)+1, img_h);
取对应点图上的坐标
icr = img(iy, ix, 1);
icg = img(iy, ix, 2);
icb = img(iy, ix, 3);
取图片对应点的颜色,r、g、b分量
pc = single([icr, icg, icb]/2^(8-bit)) * 2^(8-bit) / 256;
转换成matlab的颜色空间(r、g、b都在0~1之间)
plot画图
如果有网友想得到灰色图像,那么
在进入循环之前加上
img = rgb2gray(img);
然后把
icr = img(iy, ix, 1);
icg = img(iy, ix, 2);
icb = img(iy, ix, 3);
pc = single([icr, icg, icb]/2^(8-bit)) * 2^(8-bit) / 256;
改成
ic = img(iy, ix, 1);
pc = single([ic, ic, ic]/2^(8-bit)) * 2^(8-bit) / 256;
就行了