HD4074329S Renesas Electronics America, HD4074329S Datasheet - Page 63

• Manufacturer Part Number: HD4074329S
• Description: MCU 4-Bit HMCS400 CISC 20KB EPROM 3.3V/5V 64-Pin SDIP
• Manufacturer: Renesas Electronics America

Specifications of HD4074329S

• Package: 64SDIP
• Family Name: HMCS400
• Maximum Speed: 4.5 MHz
• Ram Size: 268 Byte
• Program Memory Size: 20 KB
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 4 Bit
• Program Memory Type: EPROM
• Number Of Programmable I/os: 35
• On-chip Adc: 4-chx8-bit
• Operating Temperature: -20 to 75 °C
• Number Of Timers: 3

LCD Controller/Driver
The MCU has an LCD controller and driver which drive four common signal pins and 24 segment pins.
The controller consists of a RAM area in which display data is stored, a display control register (LCR), and
a duty cycle/clock control register (LMR), as shown in figures 37 and 38.
Four duty cycles and the LCD clock are program-controllable, and a built-in dual-port RAM ensures that
display data can be automatically transmitted to the segment signal pins without program intervention. If a
32-kHz oscillation clock is selected as the LCD clock source, the LCD can be used even in watch mode, in
which the system clock stops.
GND
Note:
LCD: Liquid crystal display
V
V
CC
V
V
2
1
3
*
*
*
*
HD404324U, HD404326U, HD404328U and HD4074329U require external LCD voltage division resistors.
Display control
LCD duty cycle/
(LCR: $013)
(LMR: $014)
clock control
Power switch
1
register
2
register
control
power
circuit
LCD
2
2
Figure 37 Block Diagram of LCD Controller/Driver
$050
$067
Display on/off
RAM area
(dual-port
Display
RAM)
area
Duty cycle selection
Clock selection
LCD clock
common
segment
driver
driver
LCD
LCD
LCD clock
(LOR: $015)
LCD output
multiplexer
3
1
Segment/
register
R2–R5
port
4
Divided system
clock output
Divided 32-kHz
clock output
HD404328 Series
COM1
COM2
COM3
COM4
R2 /SEG1
R2 /SEG2
R5
SEG17
SEG24
0
1
3
/SEG16
59