PCIE :doubt in memory write request TLP

Comments and questions to the author of the "Down to the TLP" posts (Eli Billauer)

PCIE :doubt in memory write request TLP

Postby Guest » Thu May 11, 2017 2:19 pm

http://xillybus.com/tutorials/pci-express-tlp-pcie-primer-tutorial-guide-1

in memory write request TLP :
The Address field is simply the address to which the first data DW is written. Well, bits 31-2 of this address. Note that the two LSBs of DW 2 in the TLP are zero, so DW 2 actually reads the write address itself. Multiply 0x3f6bfc10 by four, and you get 0xfdaff040.


could u explain me why do u multiplied address by 4 :?: :?: :?:
Guest
 

Re: PCIE :doubt in memory write request TLP

Postby support » Thu May 11, 2017 2:24 pm

Hello,

Well, actually, I didn't. I multiplied the value in the address[31:2] field by 4 to obtain the actual address. If you read the contents of DW2 as a 32-bit word, you get the address itself, 0xfdaff040.

Regards,
Eli
support
 
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