MITSUBISHI MICROCOMPUTERS
4280 Group
SINGLE-CHIP 4-BIT CMOS MICROCOMPUTER for INFRARED REMOTE CONTROL TRANSMITTERS
Timer 1 start
(V10)←1
“1”
Timer 1 underflow
“0”
a
c
d
b
“H”
Port CARR output
“L”
a
c
d
b
Set the interval “b”
to reload register R1.
Set the interval “d”
to reload register R1.
Set the interval “c”
to reload register R1.
Set the interval “a” to timer 1.
Select count source CARRY
(V11)←0
Auto-control valid
(V12)←1
Carrier wave output start
Timer 1 stop
(V10)←0
“1”
“0”
Timer 1 underflow
“H”
“L”
CARRY
(Note)
“H”
“L”
Port CARR output
Register V12
“1”
“0”
Auto-control invalid Auto-control invalid
Carrier wave output start
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
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.
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 shows the logic operation selection register LO.
Table 5 Logic operation selection register LO
Logic operation selection register LO
Logic operation selection bits
at reset : 002
at RAM back-up : 002
W
L
O
1 L
O
0
1
0
1
0
Logic operation function
0
0
1
1
Exclusive logic OR operation (XOR)
OR operation (OR)
LO1
LO0
AND operation (AND)
Not available
Note: “W” represents write enabled.
MITSUBISHI
ELECTRIC
15
MITSUBISHI [ Mitsubishi Group ]
