MITSUBISHI MICROCOMPUTERS
4280 Group
SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER for INFRARED REMOTE CONTROL TRANSMITTERS
Timer 1 start
(V10)←1
Timer 1 underflow “1”
“0”
a
b
c
d
“H”
Port CARR output
“L”
a
b
c
d
Set the interval “a” to timer 1.
Select count source CARRY
(V11)←0
Set the interval “b” Set the interval “c” Set the interval “d”
to reload register R1. to reload register R1. to reload register R1.
Auto-control valid
(V12)←1
Carrier wave output start
“1”
Timer 1 underflow “0”
CARRY “H”
“L”
“H”
Port CARR output“L”
“1”
Register V12 “0”
Timer 1 stop
(V10)←0
(Note)
Carrier wave output start
Auto-control invalid Auto-control invalid
Carrier wave output stop
(V12)←0 (V12)←1 (V12)←0 (V12)←1
Note: When timer 1 is stopped, the port CARR output auto-control is terminated regardless of bit 2 (V12) of register V1.
Fig. 16 Port CARR output auto-control by timer 1
LOGIC OPERATION FUNCTION
The 4280 Group has the 4-bit logic operation function. The logic
operation between the contents of register A and the low-order 4
bits of register E is performed and its result is stored in register
A.
Table 5 Logic operation selection register LO
Each logic operation can be selected by setting logic operation
selection register LO.
Set the contents of this register through register A with the TLOA
instruction. The logic operation selected by register LO is
executed with the LGOP instruction.
Table 5 shows the logic operation selection register LO.
Logic operation selection register LO
at reset : 002
at RAM back-up : 002
W
LO1
Logic operation selection bits
LO0
LO1 LO0
Logic operation function
0 0 Exclusive logic OR operation (XOR)
0 1 OR operation (OR)
1 0 AND operation (AND)
1 1 Not available
Note: “W” represents write enabled.
MITSUBISHI
ELECTRIC
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