HI There,
I asked a question about data width and protocol convertor a month ago.(AHB 32bit <-> AXI 64bit Bridge)
And someone told me that NIC-400 Network is proper. (Thank you so much:))
But, I realize that NIC-400 isn't support AHB-Full.
I want to use AHB-FULL <-> AXI Bridge.
Is there another Option???
Thank you so much. :)
Which features of "AHB-FULL" do you want to support through to AXI ?
The original AMBA 2 AHB protocol supported multiple sources on one bus, whereas the AMBA 3 AHB-lite protocol supported by the NIC-400 only supports a single transaction source.
AHB-lite removed the multi-source support in the original AHB, which means no HBUSREQ/HGRANT arbitration support, and no SPLIT or RETRY responses returned by targets (as these were only relevant to multi-source systems).
Other than the HBUSREQ/HGRANT and SPLIT/RETRY features removed, AHB-lite is then fully AHB compatible, so is there anything from the original AHB protocol that you needed that isn't then supported ?
HI, Mr.Colin
First of all thank you for your guidance.
I have to use the feature of ahb-full like HBUSREQ/HGRANT what you said.
Because I'm designing multi-source systems.
Due to your kindly explanation, I can aware the feature of AHB-LITE and AHB-FULL.
Thank you.
Best regards,
HBUSREQ and HGRANT are used by the AHB transfer sources to request access to a shared AHB bus, but when you are converting from AHB to AXI it would be the HTRANS signal from the "granted" AHB source that would indicate a transfer request top the AXI logic.
So if you are connecting a single AHB source to an AHB to AXI conversion bridge, you would tie HGRANT high (as this is the only possible AHB source), and just ignore HBUSREQ.
If you do have multiple AHB sources, the local AHB arbiter will be using all the HBUSREQ and HGRANT signals to grant one source, and then the AHB to AXI conversion logic again just uses the HTRANS signal from this granted source as the transfer request.