Details

---

BUY MC68HC705J1ACP https://www.utsource.net/itm/p/12533330.html

Parameter	Description	Value
Device Type	8-bit microcontroller
Package	Plastic dual in-line package (PDIP)	40-pin
Operating Voltage (VCC)	Supply voltage range	4.75V to 5.25V
Clock Frequency	Internal oscillator frequency	4 MHz (nominal)
Flash Memory	Program memory	2K bytes
RAM	Data memory	128 bytes
I/O Ports	Number of I/O lines	28
Timers	Number of timers	2 (8-bit)
Interrupts	Number of interrupt sources	13
Watchdog Timer	Watchdog timer	Yes
Power Consumption	Active mode power consumption (typical)	100 mA at 5V, 4 MHz
Operating Temperature	Temperature range	-40°C to +85°C
Programming Interface	In-circuit serial programming (ICSP)	Yes
Package Marking	Device marking	MC68HC705J1ACP

Instructions for Use

1. Power Supply:

   • Ensure the supply voltage (VCC) is within the specified range of 4.75V to 5.25V.
   • Connect the ground (GND) pin to a stable ground reference.

2. Clock Configuration:

   • The internal oscillator operates at 4 MHz by default. For external clock sources, connect the clock signal to the appropriate pins as specified in the datasheet.

3. I/O Configuration:

   • Configure the I/O ports using the appropriate register settings in your program.
   • Set the direction of each port (input or output) using the data direction registers (DDRx).

4. Memory Access:

   • Program the flash memory using the ICSP interface or an external programmer.
   • Access RAM and other memory-mapped peripherals using standard read/write instructions.

5. Timer Setup:

   • Initialize the timers by setting the timer control registers (TMRx).
   • Use the timers for various timing and counting applications.

6. Interrupt Handling:

   • Enable interrupts by setting the appropriate bits in the interrupt enable register (IER).
   • Write interrupt service routines (ISRs) to handle specific interrupt events.

7. Watchdog Timer:

   • Enable the watchdog timer to reset the microcontroller if the software becomes stuck.
   • Clear the watchdog timer periodically to prevent unintended resets.

8. Programming:

   • Use a supported development environment or toolchain to write and compile your code.
   • Program the device using the ICSP interface or an external programmer.

9. Testing and Debugging:

   • Verify the operation of the microcontroller using a logic analyzer or debugger.
   • Check for any hardware or software issues by monitoring the I/O pins and memory contents.

10. Environmental Considerations:

    • Ensure the operating temperature is within the specified range to avoid damage to the device.
    • Protect the device from electrostatic discharge (ESD) during handling and installation.

(For reference only)