20. BRHC – Branch if Half Carry Flag is Cleared
20.1. Description
Conditional relative branch. Tests the Half Carry Flag (H) and branches relatively to PC if H is cleared.
This instruction branches relatively to PC in either direction (PC - 63 ≤ destination ≤ PC + 64). Parameter
k is the offset from PC and is represented in two’s complement form. (Equivalent to instruction BRBC 5,k.)
Operation:
(i) If H = 0 then PC ← PC + k + 1, else PC ← PC + 1
Syntax: Operands: Program Counter:
(i) BRHC k -64 ≤ k ≤ +63 PC ← PC + k + 1
PC ← PC + 1, if condition is
false
16-bit Opcode:
1111 01kk kkkk k101
20.2. Status Register (SREG) and Boolean Formula
I T H S V N Z C
– – – – – – – –
Example:
brhc hclear ; Branch if Half Carry Flag cleared
...
hclear: nop ; Branch destination (do nothing)
Words 1 (2 bytes)
Cycles 1 if condition is false
2 if condition is true
Atmel AVR Instruction Set Manual [OTHER]
Atmel-0856L-AVR-Instruction-Set-Manual_Other-11/2016
47
To Next Page
Loading...
Need help?
General
