CounterID<n> Counter ID registers It is IMPLEMENTATION DEFINED whether CounterID<n> is implemented in the Core power domain or in the Debug power domain 0 11 Timer CNTControlBase 0xFD0 + (4 * n) CounterID<n> RO Timer CNTReadBase 0xFD0 + (4 * n) CounterID<n> RO Timer CNTBaseN 0xFD0 + (4 * n) CounterID<n> RO Timer CNTEL0BaseN 0xFD0 + (4 * n) CounterID<n> RO Timer CNTCTLBase 0xFD0 + (4 * n) CounterID<n> RO IMPLEMENTATION DEFINED identification registers 0 to 11 for the memory-mapped Generic Timer. Timer For more information, see 'Power and reset domains for the system level implementation of the Generic Timer'. These registers are implemented independently in each of the implemented Generic Timer memory-mapped frames. If the implementation of the Counter ID registers requires an architecture version, the value for this version of the Arm Generic Timer is version 0. The Counter ID registers can be implemented as a set of CoreSight ID registers, comprising Peripheral ID Registers and Component ID Registers. An implementation of these registers for the Generic Timer must use a Component class value of 0xF. CounterID<n> is a 32-bit register. IMPLEMENTATION DEFINED 31 0 31:0 IMPLEMENTATION DEFINED. These registers must be implemented, as RO registers, in every implemented Generic Timer memory-mapped frame. For the CNTCTLBase frame, in a system that supports the Realm Management Extension, it is IMPLEMENTATION DEFINED whether Root and Realm accesses to these registers are permitted. If not permitted, these registers behave as RES0 for Root and Realm accesses. For the CNTCTLBase frame, in a system that recognizes two Security states these registers are accessible by both Secure and Non-secure accesses. For the CNTControlBase frame, in a system that supports the Realm Management Extension, the frame is implemented only in the Root physical address space, meaning these registers are implemented only in the Root physical address space. For the CNTControlBase frame, in a system that supports Secure and Non-secure physical address spaces, the frame is implemented only in the Secure physical address space, meaning these registers are implemented only in the Secure physical address space. For the CNTReadBase frame, these registers are accessible in all physical address spaces. For the CNTBaseN frames, 'CNTCTLBase status and control fields for the CNTBaseN and CNTEL0BaseN frames' describes the status fields that identify whether a frame is implemented, and for an implemented frame: Whether the CNTBaseN frame has virtual timer capability. Whether the corresponding CNTEL0BaseN frame is implemented. For an implementation that supports the Realm Management Extension, whether the CNTBaseN frame, and any corresponding CNTEL0BaseN frame, is accessible by Root and Realm accesses. For an implementation that recognizes two Security states, whether the CNTBaseN frame, and any corresponding CNTEL0BaseN frame, is accessible by Non-secure accesses. The CNTBaseN frame is always accessible by Secure accesses. 2026-03-26 20:27:25 2026-03_rel