SetRotateUnit.m

function Flag = SetRotateUnit( Serial_Obj , Angle , Cmd)
% Flag = SetRotateAngle( Serial_Obj , Angle )
% Flag : Flag==0 程序顺利执行完成
% Serial_Obj : 串口对象
% Angle 电机旋转角度 

% 这个函数用来设置转台的旋转角度的大小
% 对于此平台，电机64微步==平台0.01度
% Edited by chenguang 2015-05-28 && Email：guang@zchenguang.com
% -------------------------------------------------------------------------

% 换算角度为电机微步
Steps_Element = 32;
Angle_Element = 0.005;
Steps = Angle/Angle_Element*Steps_Element;

% Constants and varibles might be used 

% 1> Check the serial status
% if ~strcmp( Serial_Obj.Status, 'open' )
%     error('MotorSetSteps:Serial Port is closed!');
% end
if abs(Steps)>32700
    error('MotorSetSteps:Variable "Steps" is to large');
end
if Steps >= 0    % 如果不为负，则只拆分就可以，否则转换成补码的形式
    Steps_HighBits = fix( Steps / 256 );
    Steps_LowBits = Steps - Steps_HighBits*256;
else 
    Steps_Compl = 2^15 + Steps;
    Steps_LowBits = abs( Steps_Compl -  fix( Steps_Compl  / 256 )*256);
    Steps_HighBits = fix( Steps_Compl  / 256 ) + 128 ;
end


if Serial_Obj.Status ~='open'
    error('Motor:Serial Port is closed!');
end
if Serial_Obj.BytesAvailable
    fread( Serial_Obj , Serial_Obj.BytesAvailable );
end

% Get the positions
fwrite( Serial_Obj , Cmd , 'uint8' );

% 2> Confirm and write the steps to write to the device
fwrite( Serial_Obj , 2 , 'uint8' );
fwrite( Serial_Obj , 0 , 'uint8' );
fwrite( Serial_Obj , Steps_HighBits , 'uint8' );
fwrite( Serial_Obj , Steps_LowBits ,'uint8');
tic;
while toc <= abs(Steps)*0.0005  % 如果步进为0.1度，那么0.00048一步可以正常旋转，但是如果换成0.05一步，则会出现丢步
end