DESCRIPTION
The 38B5 group is the 8-bit microcomputer based on the 740 family core technology.
The 38B5 group has six 8-bit timers, a 16-bit timer, a fluorescent display automatic display circuit, 12-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 38B5 group has variations of internal memory size and packag ing. For details, refer to the section on part numbering.
For details on availability of microcomputers in the 38B5 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 some products. 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 ............................................. 24K to 60K bytes
   RAM ..........................................1024 to 2048 bytes
• Programmable input/output ports ............................................. 55
• High-breakdown-voltage output ports ...................................... 36
• Software pull-up resistors ....... (Ports P5, P61to P65, P7, P84to P87, P9)
• Interrupts .................................................. 21 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
• PWM ............................................................................ 14-bit ✕ 1
                         8-bit ✕ 1 (also functions as timer 6)
• A-D converter .............................................. 10-bit ✕ 12 channels
• Fluorescent display function ......................... Total 40 control pins
• Interrupt interval determination function ..................................... 1
• Watchdog timer ............................................................ 20-bit ✕ 1
• Buzzer output ............................................................................. 1
• 2 Clock generating circuit
   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)
• 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

APPLICATION
Musical instruments, VCR, household appliances, etc.