[Artix 7] Create the pattern to test VDMA using loopback

[skyfall133]

Hi, 

I'm learning how to use DMA, VDMA. So I choose the loopback mode to verify them and I need to make the pattern. In Dma, I easily create the pattern to test transmit in loopback mode, I just need to make to for loop to put the pattern into Tx Buffer. My pattern includes two packets, each packet has the 8-bit length like this: 

//MAX_PK_LENGTH = 8 bit
for (Index = 0; Index < 2*MAX_PK_LENGTH; Index++){
		*(TxBufferPtr+Index) = Value;
		xil_printf ("TX addr: %x  and value: %x\n\r", (unsigned int)(TxBufferPtr+Index),(unsigned int)TxBufferPtr[Index]);
		Value = (Value+1) & 0xFF;

And this way to verify: 

for (Index = 0; Index < 2*MAX_PK_LENGTH; Index++){
		if (RxBufferPtr[Index] != Value){
			xil_printf("Data error %d: %x/%x\r\n",
						    Index, (unsigned int)RxBufferPtr[Index],
						    (unsigned int)Value);
		}
		xil_printf ("RX addr: %x  and value: %x \n\r", (unsigned int)(RxBufferPtr+Index),(unsigned int)RxBufferPtr[Index]);
		Value = (Value+1) & 0xFF;
	}

 And in VDMA, I use frame video: 640x480 (1 pixel = 4 bytes). It means each frame(packet) is 0x12C000 bytes, and I don't know how to create like that frame because it 's too large to create the pattern by for loop and test. Any suggestions to create the pattern to verify in VDMA ? 

And if I use Test pattern generator, can I use the diagram below to verify loopback in VDMA? (As compare buf_0 with buf_1 after transmit done)

[florentw]

Hi @skyfall133,

I would use the solution with the VDMA, this is the easiest way for me. Yes you should be able to do as per your suggestion.

Let me know if you have any issue doing this.

Best Regards,

[skyfall133]

@florentw thanks for the reply, 

I am doing that. If I have any issue, I will tell you. 

By the way, where can I find some tutorial/source code to learn how to use test pattern generation? 

[florentw · Accepted solution]

Hi @skyfall133,

The Test Pattern Generator as an example design you can use.

I also wrote the Video Beginner Series 4 showing the TPG IP in simulation.

Regards,

[florentw]

HI @skyfall133,

Do you have any update on this?

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