ARM7 ARM 7 State Current CPU State 1 Core (Now) Current State CPU Registers 32 RW unsigned int R0 General purpose register 0 0 R1 General purpose register 1 1 R2 General purpose register 2 2 R3 General purpose register 3 3 R4 General purpose register 4 4 R5 General purpose register 5 5 R6 General purpose register 6 6 R7 General purpose register 7 7 R8 General purpose register 8 72 R9 General purpose register 9 73 R10 General purpose register 10 74 R11 General purpose register 11 75 R12 General purpose register 12 76 R13 SP R13 (SP) Stack pointer (SP) 77 R14 LR R14 (LR) Link register (LR) 78 R15 PC R15 (PC) Program counter (PC) 9 CPSR Current program status register 8 M Mode bits 0 5 T Thumb state 5 1 F SVC disable 6 1 I IRQ disable 7 1 V Overflow flag 28 1 C Carry flag 29 1 Z Zero flag 30 1 N Negative flag 31 1 Core (All) All CPU Registers 32 RW unsigned int R0_USR General purpose register 0 (User Mode) 0 R1_USR General purpose register 1 (User Mode) 1 R2_USR General purpose register 2 (User Mode) 2 R3_USR General purpose register 3 (User Mode) 3 R4_USR General purpose register 4 (User Mode) 4 R5_USR General purpose register 5 (User Mode) 5 R6_USR General purpose register 6 (User Mode) 6 R7_USR General purpose register 7 (User Mode) 7 R8_USR General purpose register 8 (User Mode) 10 R9_USR General purpose register 9 (User Mode) 11 R10_USR General purpose register 10 (User Mode) 12 R11_USR General purpose register 11 (User Mode) 13 R12_USR General purpose register 12 (User Mode) 14 R13_USR Stack pointer (User Mode) 15 R14_USR Link register (User Mode) 16 R15_USR Program counter (User Mode) 9 SPSR_USR Current program status register (User Mode) 8 M Mode bits 0 5 T Thumb state 5 1 F SVC disable 6 1 I IRQ disable 7 1 V Overflow flag 28 1 C Carry flag 29 1 Z Zero flag 30 1 N Negative flag 31 1 R8_FIQ General purpose register 8 (Fast Interrupt Mode) 18 R9_FIQ General purpose register 9 (Fast Interrupt Mode) 19 R10_FIQ General purpose register 10 (Fast Interrupt Mode) 20 R11_FIQ General purpose register 11 (Fast Interrupt Mode) 21 R12_FIQ General purpose register 12 (Fast Interrupt Mode) 22 R13_FIQ Stack pointer (Fast Interrupt Mode) 23 R14_FIQ Link register (Fast Interrupt Mode) 24 SPSR_FIQ Current program status register (Fast Interrupt Mode) 17 M Mode bits 0 5 T Thumb state 5 1 F SVC disable 6 1 I IRQ disable 7 1 V Overflow flag 28 1 C Carry flag 29 1 Z Zero flag 30 1 N Negative flag 31 1 R13_SVC Stack pointer (Supervisor Mode) 26 R14_SVC Link register (Supervisor Mode) 27 SPSR_SVC Current program status register (Supervisor Mode) 25 M Mode bits 0 5 T Thumb state 5 1 F SVC disable 6 1 I IRQ disable 7 1 V Overflow flag 28 1 C Carry flag 29 1 Z Zero flag 30 1 N Negative flag 31 1 R13_ABT Stack pointer (Abort Mode) 29 R14_ABT Link register (Abort Mode) 30 SPSR_ABT Current program status register (Abort Mode) 28 M Mode bits 0 5 T Thumb state 5 1 F SVC disable 6 1 I IRQ disable 7 1 V Overflow flag 28 1 C Carry flag 29 1 Z Zero flag 30 1 N Negative flag 31 1 R13_IRQ Stack pointer (Interrupt Mode) 32 R14_IRQ Link register (Interrupt Mode) 33 SPSR_IRQ Current program status register (Interrupt Mode) 31 M Mode bits 0 5 T Thumb state 5 1 F SVC disable 6 1 I IRQ disable 7 1 V Overflow flag 28 1 C Carry flag 29 1 Z Zero flag 30 1 N Negative flag 31 1 R13_UND Stack pointer (Undefined Mode) 35 R14_UND Link register (Undefined Mode) 36 SPSR_UND Current program status register (Undefined Mode) 34 M Mode bits 0 5 T Thumb state 5 1 F SVC disable 6 1 I IRQ disable 7 1 V Overflow flag 28 1 C Carry flag 29 1 Z Zero flag 30 1 N Negative flag 31 1