- #Rgb to vga converter circuit diagram serial
- #Rgb to vga converter circuit diagram software
- #Rgb to vga converter circuit diagram Pc
The HDMI specification requires the HDMI source to check for supported HDMI sink video modes prior to sending the video stream. The HDMI2VGA converter ensures that the proper video standard, acceptable by the video display, is sent over the HDMI link. When the board is first powered up, it reads back the VGA EDID from the monitor, programs the ADV7611 for receiving the HDMI stream, and programs the SSM2604 to output the I2S audio through its DAC. The highly efficient regulators provide the 3.3 V and 1.8 V to the devices on the board. The board uses two ADP2301 step-down switching regulators to power the board from a 5 V USB power supply. The ADuC7020 is also connected to the INT1 and RESET pins of ADV7611 and to the PSAVE pin of the ADV7125 to allow for video DAC control.
#Rgb to vga converter circuit diagram Pc
It requires an additional level shifter (for example, ADM3202) to connect to the PC using the RS232 standard.
#Rgb to vga converter circuit diagram software
In normal operation, the UART interface can also be used as a debug output or terminal during software development.
#Rgb to vga converter circuit diagram serial
They are used along with a serial programming button (connected to P0.0) and reset button to program the on-chip flash memory with an executable. The ADuC7020 also has universal asynchronous receiver-transmitter (UART) lines. The main I 2C bus contains the ADV7611 and the SSM2604 I 2C slave devices. The switch allows separating the main I 2C bus from VGA I 2C DDC lines to minimize risk of any potential conflicts (in case the monitor shares DDC I 2C with other devices or failure of VGA DDC lines). The ADuC7020 uses I 2C SDA and SCL lines that are connected via an ADG736 switch to either of the VGA display data channel (DDC) lines or to the main I 2C bus. The circuit is controlled with an ADuC7020 microcontroller. The audio line output signal impedance is 100 Ω, and an additional power amplifier stage is required for headphone or speaker connection. To ensure such an I 2S stream is sent, the ADV7611 must provide an HDMI source with the appropriate EDID content that only indicates the LPCM capability. The part can output virtually any HDMI standard however, the backend SSM2604 audio codec only accepts an I 2S stream carrying linear pulse-code modulation (LPCM) audio with a 44.1 kHz or 48 kHz sampling rate. The ADV7125 video DAC converts the digital receive stream to a VGA-compatible analog signal.Īudio processing within the converter starts with the ADV7611 that has a built-in audio packet extraction block. The ADV7611 is also capable of any conversion between the 444 and 422 sampling schemes.
This covers conversion of the following colorspaces: RGB, YCrCb (601 and 709), XVYCC (601 and 709), and others specified by the HDMI specification. The built-in color space converter (CSC) in this circuit converts any HDMI color space to an 8-bit RGB444 word suitable for driving the ADV7125 video DAC input. The ADV7611 incorporates an internal EDID RAM that provides display capabilities for the HDMI source. The ADV7611 provides the receiving solution for the HDMI inputs and has a 5 V cable detect, a hot plug detect line assertion, and DDC lines that are used for EDID purposes. The circuit was built on a 2-layer printed circuit board (PCB), and it works up to UXGA resolutions (1600 × 1200 at 60 Hz). By using industry-standard interchip connections, direct connections can be made between the receiver, codec, and video digital-to-analog converter (DAC). Step-down switching regulators allow the circuit to be powered from a USB port. Built-in EDID memory reduces the count of the parts and the real estate. A simple I 2C write can adjust brightness, contrast, or change the audio volume. The highly integrated video receiver allows video adjustments without the need for additional field-programmable gate arrays (FPGAs). There are numerous benefits of this circuit.
The HDMI receiver can also be used for video adjustments, such as brightness or contrast, and the audio codec can be used to set the volume of the audio output. HDMI-to-VGA (HDMI2VGA) Converter Block Diagram (Simplified Schematic: All Connections Not Shown) The circuit uses extended display identification data (EDID) content to ensure that the video stream from the HDMI/digital visual interface (DVI) source is at the highest possible resolution supported by the HDMI source, converter, and video graphics adapter (VGA) display. The circuit is powered from a USB cable and works for resolutions up to 1600 × 1200 at 60 Hz. It uses the low power ADV7611 high-definition multimedia interface (HDMI) receiver capable of receiving video streams up to 165 MHz. The circuit shown in Figure 1 is a complete solution for the conversion of HDMI/DVI to VGA (HDMI2VGA) with an analog audio output.