Design of Microcontroller´s Display System Based on FPGA

To solve the problem of microcontroller´s speed and resources in the high-resolution image display effectively, a method based on FPGA and expansion of SDRAM to support the microcontroller to realize image display is proposed. The communication between STM32 and FPGA is implemented by simulating Intel8080 interface protocols, depending on the coordinate position, the collected data is saved to the specified address in the SDRAM, and then reads them out to VGA controller in form of VGA display interface standard, last, sends the row, field synchronous signal and image data to LVDS transmitter which can convert parallel data into serial of low voltage differential signal so that LCD panel can display. The whole operation above is controlled by FPGA. We adopt soft IP core “altlvds_tx” of FPGA to realize image data format conversion. This paper not only gives the detailed design of the internal FPGA, including VGA controller, SDRAM controller, 8080 interface protocol and LVDS transmitter modules, but also provides the actual test results and chart analysis. This system has been successfully applied in the digital language learning products.