HT82K68 Holtek Semiconductor Inc, HT82K68 Datasheet - Page 34

• Manufacturer Part Number: HT82K68
• Description: Multimedia Keyboard Encoder OTP
• Manufacturer: Holtek Semiconductor Inc

SBC A,[m]
Description
Operation
Affected flag(s)
SBCM A,[m]
Description
Operation
Affected flag(s)
SDZ [m]
Description
Operation
Affected flag(s)
SDZA [m]
Description
Operation
Affected flag(s)
Subtract data memory and carry from the accumulator
The contents of the specified data memory and the complement of the carry flag
aresubtractedfromtheaccumulator, leaving the result in the accumulator.
ACC ¬ ACC+[m]+C
Subtract data memory and carry from the accumulator
The contents of the specified data memory and the complement of the carry
flag are subtracted from the accumulator, leaving the result in the data
memory.
[m] ¬ ACC+[m]+C
Skip if decrement data memory is 0
The contents of the specified data memory are decremented by 1. If the result
is 0, the next instruction is skipped. If the result is 0, the following instruc-
tion, fetched during the current instruction execution, is discarded and a
dummy cycle is replaced to get the proper instruction (two cycles). Otherwise
proceed with the next instruction (one cycle).
Skip if ([m]-1)=0, [m] ¬ ([m]-1)
Decrement data memory and place result in ACC, skip if 0
The contents of the specified data memory are decremented by 1. If the result
is 0, the next instruction is skipped. The result is stored in the accumulator
but the data memory remains unchanged. If the result is 0, the following in-
struction, fetched during the current instruction execution, is discarded and
a dummy cycle is replaced to get the proper instruction (2 cycles). Otherwise
proceed with the next instruction (1 cycle).
Skip if ([m]-1)=0, ACC ¬ ([m]-1)
TC2
TC2
TC2
TC2
¾
¾
¾
¾
TC1
TC1
TC1
TC1
¾
¾
¾
¾
TO
TO
TO
TO
¾
¾
¾
¾
Preliminary
PD
PD
PD
PD
¾
¾
¾
¾
34
OV
OV
OV
OV
¾
¾
Ö
Ö
¾
¾
Z
Ö
Z
Ö
Z
Z
AC
AC
AC
AC
¾
¾
Ö
Ö
¾
¾
C
C
C
C
Ö
Ö
HT82K68E
August 8, 2000