hello, can anybody tell me how to use alt_up_video_dma_draw function in quartus 2018

Hi, I am assuming your design configured all the IP setting correctly and there is no design timing closure concern else this is the first step that you need to check. - For instance, if you drill further into VGA_Subsystem then it should show you the exact IP name that can match back with "video IP suite" doc For the onchip memory issue debug - Have you managed to isolate the issue is with memory write issue, memory read issue or memory content corruption issue or VGA display IP issue ? For memory write/read issue : - Memory write/read issue could be due to address mapping issue or design timing closure issue For memory content corrupted issue : - How do you generate the onchip memory hex file content ? - Do you have other hex file content that you can load into to compare video output result ? For VGA display IP issue : - You want to checkout video IP suite doc to ensure you configure all the setting correctly that match with your hardware board - You can also keep your design simple for debug to slowly disable IP feature in VGA subsystem to find out where is the culprit. Thanks. Regards, dlim