Programmable Devices
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19663 Discussions

PCie BAR to memory mapped slave

Honored Contributor II

hi guys!! 


Well, I've got trouble with sending a some data to memory mapped slave.  

My PCIe just has one BAR. 

That Bar has a size of 4kbytes - 12 bits and my memory mapped slave has a 10 bits of address width and 32 data width  

(memory mapped slave has address are 0x0000_0000 to 0x0000_0fff). 


So my questions are: 

1.- if I want to send data to memory slave, How should I fill BAR?:confused:....... Bar has size of 4KBytes and I dont know which bits are of datas and address. 

2.- Why dooes BAR has 12 bits if my memory mapped slave has 10 bits??:confused: 


Well, Iill be thanking for your replys!!
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Honored Contributor II

The BAR is for bytes. Your memory is four bytes. 

Memory address of 10 bits plus 2 bits to address the byte = 12.