NEC 78K/0 Series - Manual (Page 114)

114
CHAPTER 5 EXPLANATION OF INSTRUCTIONS
User's Manual U12326EJ4V0UM
Branch if True and Clear
BTCLR
Conditional Branch and Clear by Bit Test (Byte Data Bit = 1)
[Instruction format] BTCLR bit, $addr16
[Operation] PC
← PC+b+jdisp8 if bit = 1, then bit ← 0
[Operand]
Mnemonic Operand(bit,$addr16) b(Number of bytes)
BTCLR saddr.bit, $addr16 4
sfr.bit, $addr16 4
A.bit, $addr16 3
PSW.bit, $addr16 4
[HL].bit, $addr16 3
[Flag]
bit =PSW.bit In all other cases
Z AC CY Z AC CY
Ч Ч Ч
[Description]
• If the 1st operand (bit) contents have been set (1), they are cleared (0) and branched to the address specified
by the 2nd operand.
If the 1st operand (bit) contents have not been set (1), no processing is carried out and the subsequent
instruction is executed.
• When the 1st operand (bit) is PSW.bit, the corresponding flag contents are cleared (0).
[Description example]
BTCLR PSW.0, $356H; When bit 0 (CY flag) of PSW is 1, the CY flag is cleared to 0 and branched to address
0356H (with the start of this instruction set in the range of addresses 02D4H to
03D3H).