Copyright © 2003-2021 Arm Limited or its affiliates. All rights reserved.
ARM IHI 0022H.c (ID012621)
AMBA
®
AXI and ACE
Protocol Specification
ii Copyright © 2003-2021 Arm Limited or its affiliates. All rights reserved. ARM IHI 0022H.c
Non-Confidential ID012621
AMBA AXI and ACE
Protocol Specification
Copyright © 2003-2021 Arm Limited or its affiliates. All rights reserved.
Release Information
The following changes have been made to this specification:
Note that issue E.a, the first publication of issue E of this specification, was originally identified as issue E.
Issues B and C of this document included an AXI specification version, v1.0 and v2.0. These version numbers have been
discontinued to remove confusion with the AXI versions AXI3 and AXI4.
Change history
Date Issue Confidentiality Change
16 June 2003 A Non-Confidential First release
19 March 2004 B Non-Confidential First release of AXI specification v1.0
03 March 2010 C Non-Confidential First release of AXI specification v2.0
03 June 2011 D-2c Non-Confidential Public beta draft of AMBA AXI and ACE Protocol Specification
28 October 2011 D Non-Confidential First release of AMBA AXI and ACE Protocol Specification
22 February 2013 E Non-Confidential Second release of AMBA AXI and ACE Protocol Specification
18 December 2017 F Non-Confidential EAC-0 release of version F.
New interfaces defined for AMBA protocol: AXI5, AXI5-Lite,
ACE5, ACE5-Lite, ACE5-LiteDVM, ACE5-LiteACP.
21 December 2017 F.b Non-Confidential EAC-1 release to address issues found with the EAC-0 release of
release F.
No change in content compared to the EAC-0 version.
30 July 2019 G Non-Confidential EAC-0 release of version G.
New optional features defined for AMBA 5 interface variants.
31 March 2020 H Non-Confidential EAC-0 release of version H.
New optional features defined for AMBA 5 interface variants.
11 January 2021 H.b Non-Confidential Regularized terminology to use Manager to indicate the agent that
initiates transactions and Subordinate to indicate the agent that
receives and responds to requests.
26 January 2021 H.c Non-Confidential Corrected error in table D13-22 for AxADDR[15]
ARM IHI 0022H.c Copyright © 2003-2021 Arm Limited or its affiliates. All rights reserved. iii
ID012621 Non-Confidential
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Non-Confidential ID012621
AMBA SPECIFICATION LICENCE
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