3-wire spi, LCD driver for HX8369

qiujiao

3-wire spi, LCD driver for HX8369 [Copy link]

I am now working on a LCD driver for HX8369, and the CPU is STM32F429. My question is how to use 3-wire SPI (cs clk sda) to initialize the LCD. The format of the driver given to me by the manufacturer is: send the register address first, and then send the register data. Write_3Spi_cmd(0x0001); Write_3Spi_data(0x6300); Write_3Spi_cmd(0x0002); Write_3Spi_data(0x0200); Write_3Spi_cmd(0x0003); Write_3Spi_data(0x6564); ................................................................................... My question is, when using spi to send data to LCD, (there are only three lines of spi), how to distinguish whether the data is sent is address or data, how to implement it in the program? Save the children! ! ! ! ! ! ! ! ! Save the children!!!!!!!!!!!! Save the children!!!!!!!!!!!!!!!!!

ckvlhf

Look at the data sheet. From your description, it may be that the register address is used to identify data or commands. What you write to the control register is a command, and what you write to the display buffer register is data. It may be like this. You can also look at the differences between the write data and write command functions provided by the manufacturer, and reverse the process!

qiujiao

ckvlhf posted on 2019-4-4 14:24 Look at the data sheet. From your description, it seems that you rely on the register address to identify data or commands. What you write to the control register is the command, and what you write to the display...

Thank you. How do you identify which register to write to? When spi is sending, do you compare the content sent by one bit?

qiujiao

HX8238

ckvlhf

qiujiao posted on 2019-4-4 14:37 Thank you, how do you identify which register to write to? Is it when spi sends, one bit is compared with the content sent?

I don't know about this either, you need to read the data sheet carefully. Generally, these data formats and timing diagrams are in the manual.

apslsai

SPI data is not 8 bits, but 9 bits. The highest bit represents command or data. For example, 0x00** represents command and 0x01** represents data.