官方的解释如下 网址
http://processors.wiki.ti.com/index.php/Audio_Capacitive_Touch_BoosterPack_Virtual_Registers_and_Commands#SIDxx_command
SETSC command
Command to set up the horizontal scroll. Use this command with $param register to set up the configuration parameter of the scoll. The parameter define the direction, the speed and the scrolling area. After isssuing this command, to start the scroll, issue the SCON command. To stop it, issue the SCOFF command.
分析 Test_ACTBP 函数
1 调用了命令 UIF_CMD_SETVP
根据手册上说的
SETVP command
Command to set the viewport on the display frame buffer. A viewport is a rectangular area of the frame buufer, the content of which is rendered on the screen of display. On many display controllers, the size of display screen is smaller than the size of the display frame buffer. Only a partial area of display frame buffer can be displayed at once on the display screen. SERTVP command is used to define "the area of interest to be doisplayed on the screen. The coordinate of the area of interset is defined by $param register. The coordinate parameter $param=0xpqrs means the origin of the viewport is located in vertical 0xpq "dot" postion and 0xrs character postiton.
应该是设置屏幕上显示的视点
2 分4次写入需要显示的四行内容
使用SIDxx 命令 设置了每行内容对应的ID (均为05)
使用SETCUR 命令 设置光标在0 1 2 3 行
使用PRTSxx 命令进行显示
注意:以上显示内容是在 virtual screen 即虚拟屏幕上显示的
(Send SETVP command to display on screen)
3 调用SETVP命令将虚拟内容显示在实际屏幕上