DESCRIPTION

The 38B7 group is the 8-bit microcomputer based on the 740 family core technology.

The 38B7 group has six 8-bit timers, one 16-bit timer, a fluorescent display automatic display circuit, 16-channel 10-bit A-D converter, a serial I/O with automatic transfer function, which are available for controlling musical instruments and household appliances.

The 38B7 group has variations of internal memory type. For details, refer to the section on part numbering.

For details on availability of microcomputers in the 38B7 group, refer to the section on group expansion.

Built-in pull-down resistors connected to high-breakdown voltage ports are available by specifying with the mask option in the mask ROM version. For the details, refer to the section on the mask option of pull-down resistor.

FEATURES

• Basic machine-language instructions ....................................... 71

• The minimum instruction execution time .......................... 0.48 µs

(at 4.19 MHz oscillation frequency)

• Memory size

ROM ........................................................ 60K bytes

RAM .......................................................2048 bytes

• Programmable input/output ports ............................................. 75

• High-breakdown-voltage output ports ...................................... 52

• Software pull-up resistors . (Ports P64 to P67, P7, P80 to P83, P9,

PA, PB)

• Interrupts .................................................. 22 sources, 16 vectors

• Timers ........................................................... 8-bit ✕ 6, 16-bit ✕ 1

• Serial I/O1 (Clock-synchronized) ................................... 8-bit ✕ 1

(max. 256-byte automatic transfer function)

• Serial I/O2 (UART or Clock-synchronized) .................... 8-bit ✕ 1

• Serial I/O3 (Clock-synchronized) ................................... 8-bit ✕ 1

• PWM ............................................................................ 14-bit ✕ 1

8-bit ✕ 1 (also functions as timer 6)

• A-D converter .............................................. 10-bit ✕ 16 channels

• D-A converter ................................................................ 1 channel

• Fluorescent display function ......................... Total 56 control pins

• Interrupt interval determination function ..................................... 1

(Serviceable even in low-speed mode)

• Watchdog timer ............................................................ 16-bit ✕ 1

• Buzzer output ............................................................................. 1

• Two clock generating circuits

Main clock (XIN–XOUT) .......................... Internal feedback resistor

Sub-clock (XCIN–XCOUT) .......... Without internal feedback resistor

(connect to external ceramic resonator or quartz-crystal oscillator)

• Power source voltage

In high-speed mode ................................................... 4.0 to 5.5 V

(at 4.19 MHz oscillation frequency and high-speed selected)

In middle-speed mode ........................................... 2.7 to 5.5 V (*)

(at 4.19 MHz oscillation frequency and middle-speed selected)

In low-speed mode ................................................ 2.7 to 5.5 V (*)

(at 32 kHz oscillation frequency)

(*: 4.0 to 5.5 V for Flash memory version)

• Power dissipation

In high-speed mode .......................................................... 35 mW

(at 4.19 MHz oscillation frequency)

In low-speed mode ............................................................. 60 µW

(at 32 kHz oscillation frequency, at 3 V power source voltage)

• Operating temperature range ................................... –20 to 85 °C

● Supply voltage ................................................. VCC = 5 V ± 10

● Program/Erase voltage ............................... VPP = 11.7 to 12.6 V

● Programming method ...................... Programming in unit of byte

● Erasing method

Batch erasing ........................................ Parallel/Serial I/O mode

Block erasing .................................... CPU reprogramming mode

● Program/Erase control by software command

● Number of times for programming/erasing ............................ 100

● Operating temperature range (at programming/erasing)

..................................................................... Normal temperature

APPLICATION

Musical instruments, VCR, household appliances, etc.