====== CFMEGA2 =====
This is an Arduino Mega compatible CPU module. It is designed to be used for GPIO, communication, ADC, NTC (temperature), etc.

  * The CPU module must be located on the far left. Connect the I/O module to the right.
  * Up to 16 I/O modules can be connected to one CPU module.

[[https://comfiletech.com/embedded-controller/cfmega2-cpu-module/|View at our online store]].
===== MCU Details=====

  * MCU: ATMega2560
  * Program memory: 256KB
  * SRAM memory: 8KB
  * EEPROM: 4KB
=====Device Details=====

  * Power supply: **DC 12~24V**((The capacity of the power supply connected here must be at least twice as large as the sum of the current consumption of all connected modules.))
  * CPU module current consumption: 0.5W
  * Communication: **CH1 : RS232C, CH2 : RS232C, CH3 :  RS485 **
  * I2C : 1 (Can connect QWIIC Modules)
  * GPIO: 8 **(7 x PWM) 5V input/output**
  * INT : 2 (External Interrupt Input, 5V input)
  * ADC: 8 **(0~20mA - 4 channels, 0~10VDC - 4 channels)**
  * STATUS LED : 13=LED, 22=RUN, 23=ERROR
  * Temperature: 1 (NTC, measurement range -40~99℃, error +/- 1 degree)

=====Description of each part=====

{{ :modularfaduino:cfmega2_desc.png?nolink |}}

 * What is QWIIC? This is a product line of Arduino I2C peripherals sold by Sparkfun, USA. [[https://www.sparkfun.com/qwiic?__hstc=60407538.4b44870ec4a577029c49e44b73bd3bee.1716249600061.1716249600062.1716249600063.1&__hssc=60407538.1.1 716249600064&__hsfp=2770298663&gad_source=1&gclid=Cj0KCQjwhb60BhClARIsABGGtw-WwnEUOz4XK6vLKRqCMOMQY0uLOygX8VLSQokoFdw3Vu2qW3XFWrQaAhjaEALw_wcB|Reference link]]

===== About GPIO =====

The GPIO port is a port that can be used for 5V input/output or PWM output. In fact, it is the same as the I/O terminal on a regular Arduino. However, a TVS diode for surge blocking is installed internally.


===== About RS485 (Channel 3) =====

The RS485 port assigned to Channel 3 is a port that uses the MAX13487 chip, which automatically switches the transmission and reception directions. Therefore, there is no need for users to handle sending/receiving directly.

===== About Power Connection =====

Please connect a voltage between DC12 and 24V into one of the DC jack and terminal blocks. 
Determine the power capacity according to the total number of connected I/O modules. 
If there are less than five, 24V 1A is suitable. If it is more than that, choose a larger capacity.
=====Example program=====
** - LED blinking **: This is a program that blinks the LED.
<code c>
const int StatusLED = 13;
void setup() {
 pinMode(StatusLED, OUTPUT);
}
void loop() {
 digitalWrite(StatusLED, HIGH);
 delay(1000);
 digitalWrite(StatusLED, LOW);
 delay(1000);
}
</code>

** - ADC analog input**: This is a program that receives current/voltage input.  Additional logic is required to convert the raw digital value (0~1024) to units like milliamps or voltage.

<code c>
void setup() {
 Serial.begin(9600);
}
void loop() {
 int current_raw_value = analogRead(A0);
 int voltage_raw_value = analogRead(A5);

 Serial.print(" Current Raw Value = "); Serial.print(current_raw_value ) ; Serial.print("\r\n" );
 Serial.print(" Voltage Raw Value = "); Serial.print(voltage_raw_value ); Serial.print("\r\n" );
 delay(200);
}
</code>
** - NTC Temperature**: NTC temperature measurement program. (Measurement range -40 ~ 99℃ / error +/-1 degree)
  * Use after registering “CFMEGA.h” library
  * Read temperature value with ''ntcRead_a4()'' function
  * NTC sensor sold separately 


<code c> int16_t ntcRead_a4(void);</code>

<code c>
#include "CFMEGA.h"
void setup() {
 Serial.begin(9600);
}
void loop() {
 int NTC_a4 = ntcRead_a4();
 Serial.print(" TEMP = "); Serial.print(NTC_a4) ; Serial.print("\r\n" );
 delay(1000);
}
</code>

** - RS232 communication**: Eco communication program for channel 1 (Tx1, Rx1).
<code c>
void setup() {
 Serial.begin(9600);
 Serial1.begin(9600);
}
void loop() {
 if (Serial1.available() > 0) {
 char rx_Byte = Serial1.read();
 Serial.print("I received: ");
 Serial.print(rx_Byte);

 Serial1.print(rx_Byte);
 }
}
</code>

===== Power Supply =====

If the total number of connected modules is 8 or less, a 24V, 1A SMPS is suitable. If the total number is 8 or more, use a 24V, 2A SMPS.

[[modularfaduino:index|Modular FADUINO]]