RS232 to TTL Problem

Development Tools IDE 1.x
1

Hi.

I want to drive the motor driver through serial communication.

But it doesn't work through Arduino.

Serial Port Configuration (Please refer to the attached serial communication)

• 115200 bits / s

• 8-bit data

• 1 Start bit

• 1 Stop bit

• No Parity

Protocol command start from blank, end of enter.

First, the current situation is as follows.

  1. Motor Controller - RS232 to USB - TeraTerm of Computer (Working)
  2. Motor Controller - RS232 to USB - Arduino Serial Monitor (including CR) on the computer (Working)
  3. Motor Controller - RS232 to TTL - Arduino (Not working)
  4. PC - USB to RS232 - RS232 to TTL - Arduino (Working)

Please refer to the image

The module in use is the MAX3232 RS232 to TTL converter module [SZH-CVBE-009].

Motor controller manual and serial communication manual are attached.

Let me tell you the voltage on the motor controller.
When not connected to Rs232 to TTL: -5.3V at Tx (2), + 0V at Rx (3)
When connecting to Rs232 to TTL: -1.39V at Tx (2), -56mV at Rx (3)

When sent in this way
!M 100 100 (including CR)
the motor does not work.

Changing the Tx and Rx pins on the motor controller side does not work.
Changing the Tx and Rx pins on the MCU side does not work.

The source code below is the current code.

void setup(){
  Serial.begin(115200);
  Serial1.begin(115200);
}

void loop(){
  if(Serial.available() > 0 ){
    String typing = Serial.readString();
    Serial1.print(typing);
  }
  
  if(Serial1.available() > 0 ){
    String str = Serial1.readString();
    Serial.print(str);

  }
}

The transmitted signal is
?D
!M 100 100
(Carriage return included).

I have been struggling for days. Please help me

KYDBL4850-2E.pdf (429 KB)

Protocol of Serial Port.pdf (144 KB)

2

Solved. Thank you.

3

How did you solve it ?
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