Hi,
I have created a custom board for the Raspberry Pi Compute Module 4 and also have the Raspberry Pi IO board for validation.
On my custom IO board, HDMI1 is connected to a standard HDMI connector, and HDMI0 is associated with a Texas TFP401 RGB converter IC.
On the Raspberry Pi IO board, I can successfully connect the screen, and it displays correctly. However, on my custom board, during booting, the screen initially shows RGBY colours and then goes to a "no signal received" mode.
I've captured the waveform on the HDMI connector side, and all the pins show 3.3V. The CLK+ and CLK- pins initially show square pulses when the RGBY colours are displayed, but once the screen goes black, the CLK+ and CLK- pins remain at 3.3V.
I thought it might be a power supply issue, so I directly provided 5V from a small DC-DC converter that can supply up to 5A, but the problem persists.
Questions:
What measurements should I take on the board to check if the HDMI is working correctly?
Apart from checking the HDMI signal, what are other ways to verify that the Raspberry Pi is booting properly and how can I connect it to a laptop for further diagnostics?
Any suggestions or guidance on what might be causing this issue would be greatly appreciated.
Thank you!
I have created a custom board for the Raspberry Pi Compute Module 4 and also have the Raspberry Pi IO board for validation.
On my custom IO board, HDMI1 is connected to a standard HDMI connector, and HDMI0 is associated with a Texas TFP401 RGB converter IC.
On the Raspberry Pi IO board, I can successfully connect the screen, and it displays correctly. However, on my custom board, during booting, the screen initially shows RGBY colours and then goes to a "no signal received" mode.
I've captured the waveform on the HDMI connector side, and all the pins show 3.3V. The CLK+ and CLK- pins initially show square pulses when the RGBY colours are displayed, but once the screen goes black, the CLK+ and CLK- pins remain at 3.3V.
I thought it might be a power supply issue, so I directly provided 5V from a small DC-DC converter that can supply up to 5A, but the problem persists.
Questions:
What measurements should I take on the board to check if the HDMI is working correctly?
Apart from checking the HDMI signal, what are other ways to verify that the Raspberry Pi is booting properly and how can I connect it to a laptop for further diagnostics?
Any suggestions or guidance on what might be causing this issue would be greatly appreciated.
Thank you!
Statistics: Posted by MAX0903 — Mon Aug 05, 2024 12:46 pm — Replies 1 — Views 30