HD4074329S Renesas Electronics America, HD4074329S Datasheet - Page 60

• 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

HD404328 Series
A/D Converter
The MCU has a built-in A/D converter that uses a sequential comparison method with a resistor ladder. It
can measure four analog inputs with an eight-bit resolution. As shown in the block diagram of figure 34,
the A/D converter has a four-bit A/D mode register, a one-bit A/D start flag, and a four-bit plus four-bit
A/D data register.
A/D Mode Register (AMR: $016): Four-bit write-only register which selects the A/D conversion period
and indicates analog input pin information. Bit 0 of the AMR selects the A/D conversion period, and bits 2
and 3 select a channel, as shown in figure 35.
A/D Start Flag (ADSF: $020, Bit 2): One-bit flag that initiates A/D conversion when 1 is written to it.
At the completion of A/D conversion, the converted data is stored in the A/D data register and the ADSF is
cleared. Refer to figure 35.
Note: Use the SEM and SEMD instructions to write data to the ADSF, but make sure that the ADSF is
56
AN
AN
AN
AN
AV
AV
CC
SS
0
1
2
3
not written to during A/D conversion.
A/D mode register
Internal bus line (S2)
(AMR: $016)
Operation mode signal
(Stop mode, Watch mode, Subactive mode: Value is 0)
Figure 34 A/D Converter Block Diagram
2
Comparator
+
–
4
1
(ADSF: $020)
A/D start flag
Control logic
1
1
A/D data register
(ADRL: $017,
ADRU: $018)
Internal bus line (S1)
Counter
4
4
IFAD