Little endian on 8-bit in Serial GPIF II

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E_521156
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Hi,
I am using Serial out GPIF II. I know that it is only support LSB first and it is only on 8-bit.
So when i used 32-bit data width also it send from LSB on each 8 bit not whole 32-bit.
for example,  for 0x3F0158F1, I can see in serial out(pin 15): 11111100   10000000   00011010  10001111
is there any way that I could sent LSB first(or MSB ) on 32-bit?
Thanks

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Rashi_Vatsa
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Hello,

I checked this at my end.

In the control center i sent AFA83A90 but in the control center AF is the LSB and 90 is the MSB.

gpif.PNG

And similarly it sent on the output line (DQ 15).gpif!.PNG

So if you want the other way round,the data need to be sent in similar manner from the control center

Please let me know if any queries on this

Regards,

Rashi

Regards,
Rashi

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Rashi_Vatsa
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Hello,

I didn't understand the question well.

Please let me know how do you send 32 bits data? Is it through the control center?

Also confirm what configuration are you using for serial out i.e packing and wordsize

Regards,

Rashi

Regards,
Rashi
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Hi,

I am using the firmware in Serial IN Interface in GPIF II    for serial OUT.
It is set for 32-bit. So I received SOF every 32-bit.

As I mentioned in last post, when I send a 32-bit data by control center, and look at the pin 15 on oscilloscope, I can see that every 8-bit is sending in LSB not whole 32-bit.
For example:(I attached 2 images)
I send 0x3F0158F1 by control center. I can see in serial out(pin 15):
11111100  10000000  00011010  10001111

which is LSB on each 8-bit not on 32-bit

But my expectation from a 32-bit LSB is: 

10001111 00011010  10000000  11111100 

Thanks

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Rashi_Vatsa
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Moderator
Moderator
5 likes given 500 solutions authored 1000 replies posted

Hello,

I checked this at my end.

In the control center i sent AFA83A90 but in the control center AF is the LSB and 90 is the MSB.

gpif.PNG

And similarly it sent on the output line (DQ 15).gpif!.PNG

So if you want the other way round,the data need to be sent in similar manner from the control center

Please let me know if any queries on this

Regards,

Rashi

Regards,
Rashi
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Hi,
Thanks for your reply.

yes, I understand. But it is a little hard, when you want to send a hex file. you should change the order of each 4 bytes.
I thought maybe there is a way for that.

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Rashi_Vatsa
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Hello,

The way data is sent from control center is explained in previous response. If you want to send the data as you mentioned, you can either modify the file you are sending or can develop a custom application

Regards,

Rashi

Regards,
Rashi
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