PD64A_15 Datasheet, PDF (19/66 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCONTROLLERS FOR INFRARED REMOTE CONTROL TRANSMISSION

µPD64A, 65
3.2.4 S2 port (bit 1 of P1)
The S2 port is an input port.
Use of a STOP mode release for the S2 port can be specified by bit 3 of the P4 register.
When using this port as a key input from a key matrix, enable the use of the STOP mode release (bit 3 of P4
register is set to 1) (at this time, a pull-down resistor is connected internally). When the STOP mode release is
disabled (bit 3 of P4 register is set to 0), this port can be used as an input port that does not release the STOP
mode even if the release condition is established (at this time, a pull-down resistor is not connected internally).
The state of the pin can be read in both cases.
After reset, the pin is set to input mode in which the STOP mode release is disabled, and enters a high-impedance
state.
3.3 Control Register 0 (P3)
Control register 0 consists of 8 bits. The contents that can be controlled are as shown below.
After reset, the register becomes 0000 0011B.
Table 3-4. Control Register 0 (P3)
Bit
Name
b7
—
Set
0
value
1
After reset
Fixed
to “0”
0
b6
b5
b4
DP (Data Pointer)
DP10^Note DP9
DP8
0
0
0
1
1
1
0
0
0
b3
TCTL
b2
CARY
b1
MOD1
b0
MOD0
1/1
ON
Refer to Table 3-5.
1/2
OFF
0
0
1
1
b0, b1: These bits specify the carrier frequency and duty ratio of the REM output.
b2: This bit specifies the availability of the carrier of the frequency specified by b0 and b1.
“0” = ON (with carrier); “1” = OFF (without carrier; high level)
b3: This bit changes the carrier frequency and the timer clock’s frequency division ratio.
“0” = 1/1 (carrier frequency: The specified value of b0 and b1; timer clock: fX/64)
“1” = 1/2 (carrier frequency: Half of the specified value of b0 and b1; timer clock: fX/128)
Table 3-5. Timer Clock and Carrier Frequency Settings
b3
0
1
b2
0
1
0
1
b1
0
0
1
1
×
0
0
1
1
×
b0
0
1
0
1
×
0
1
0
1
×
Timer Clock
fX/64
fX/128
Carrier Frequency (Duty Ratio)
fX/8 (Duty 1/2)
fX/64 (Duty 1/2)
fX/96 (Duty 1/2)
fX/96 (Duty 1/3)
Without carrier (high level)
fX/16 (Duty 1/2)
fX/128 (Duty 1/2)
fX/192 (Duty 1/2)
fX/192 (Duty 1/3)
Without carrier (high level)
b4, b5, b6: These bits specify the higher 3 bits (DP8, DP9 and DP10) of ROM’s data pointer.
Note Set DP10 of the µPD64A to 0.
Remark ×: don’t care
Data Sheet U14380EJ3V0DS00
17