ML-808GXの圧力を変更する

#!/usr/bin/env python
import sys

if len(sys.argv)<2:
    command = "04DI  "
else:
    command = sys.argv[1]
print("Command:",command)
s = 0x0
for c in command:
    s = s - (ord(c))

ubyte = (s & (0b11110000)) >> 4
lbyte =  s & 0b00001111
ubyteChar = hex(ubyte).replace('0x','').upper()
lbyteChar = hex(lbyte).replace('0x','').upper()
print("Checksum:",hex(ord(ubyteChar)),hex(ord(lbyteChar)))
command_full = []
command_full.append(hex(0x02))
for c in command:
    command_full.append(hex(ord(c)))
command_full.append(hex(ord(ubyteChar)))
command_full.append(hex(ord(lbyteChar)))
command_full.append(hex(0x03))

print("whole command:",command_full)

実行
./calc.py

Command: 0EPH  CH001P2000
Checksum: 0x38 0x35
whole command: ['0x2', '0x30', '0x45', '0x50', '0x48', '0x20', '0x20', '0x43', '0x48', '0x30', '0x30', '0x31', '0x50', '0x32', '0x30', '0x30', '0x30', '0x38', '0x35', '0x3']

CH1を200.0kPaに変更するときの通信プロシージャ(コマンド：0EPH CH001P2000)

0x05送信

• >0x06返ってくる
• >コマンド送信：['0x2', '0x30', '0x45', '0x50', '0x48', '0x20', '0x20', '0x43', '0x48', '0x30', '0x30', '0x31', '0x50', '0x32', '0x30', '0x30', '0x30', '0x38', '0x35', '0x3']
• >stx 0sA02D ext（成功メッセージA0）受信
• >0x04送信（これが必要）

Arduinoコード

#include <SoftwareSerial.h>
#define STX 0x02
#define ETX 0x03
#define SPACE 0x20
#define ENQ 0x05
#define ACK 0x06
#define EOT 0x04

SoftwareSerial mySerial(6, 7); //232_TX,232_RX

void setup() {
	Serial.begin(19200);
	// Serial3.begin(9600);
	mySerial.begin(19200);
	delay(1000);

	// String base_command = "04DI  ";
	// sendMessageBytes(base_command);
	// String base_command = "0EPH  CH001P2000";
	// sendMessageBytes(base_command);
}

void loop() {
	//message to change pressure (for specific channel)
	//format: stx 0EPH__CHXXXPXXXX?? etx
	//Channel: 0-399
	//20.0[kPa]-800.0[kPa]
    //Set channel 1 to 400.0[kPa]
	
	for(int i=0;i<4;i++){
		int pressure = (i+1)*1000;
		String pressure_string = String(pressure);
		String base_command = "0EPH  CH001P";
		String p = base_command+pressure_string;
		sendMessageBytes(p);
		delay(10);
	}
	
	// delay(1000);
}

void sendMessageBytes(String command_and_data){
	int string_length = command_and_data.length();
	char buf[string_length+1]; //length+1 (null terminator \0=0x00 in ASCII)
	command_and_data.toCharArray(buf,string_length+1);

	byte result = 0x00;
	for (int i=0;i<string_length;i++){
		result = result - buf[i];
	}
	// byte result = 0x00 - 0x30 - 0x34 - 0x44 - 0x49 - 0x20 - 0x20; //-305->two's complement of 305->0b011001111->0xCF
	byte ubyte = ((result & 0b11110000) >> 4) & 0b11111111;
	byte lbyte = result & 0b00001111;

	char ubyteChar[2];
	char lbyteChar[2];
	sprintf(ubyteChar,"%x",ubyte);
	sprintf(lbyteChar,"%x",lbyte);

	mySerial.write(ENQ);
	delayMicroseconds(100);
    mySerial.write(STX); 
    mySerial.write(buf,string_length); //do not send null terminator
  	mySerial.print(ubyteChar[0]);
  	mySerial.print(lbyteChar[0]);
    mySerial.write(ETX); 
	delayMicroseconds(100);
	mySerial.write(EOT);
}

シリアルポートを開いて送信するスクリプトにした

#!/usr/bin/env python
import sys
import time
import serial

STX = 0x02
ETX = 0x03
SPACE = 0x20
ENQ = 0x05
ACK = 0x06
EOT = 0x04
CAN = 0x18

if len(sys.argv)<2:
    command = "04DI  "
else:
    command = sys.argv[1]
print("Command:",command)
s = 0x0
for c in command:
    s = s - (ord(c))

ubyte = (s & (0b11110000)) >> 4
lbyte =  s & 0b00001111
ubyteChar = hex(ubyte).replace('0x','').upper()
lbyteChar = hex(lbyte).replace('0x','').upper()
print("Checksum:",hex(ord(ubyteChar)),hex(ord(lbyteChar)))
command_full = []
command_full_number = []
command_full.append(hex(0x02))
command_full_number.append(0x02)
for c in command:
    command_full.append(hex(ord(c)))
    command_full_number.append(ord(c))
command_full.append(hex(ord(ubyteChar)))
command_full.append(hex(ord(lbyteChar)))
command_full.append(hex(0x03))
command_full_number.append(ord(ubyteChar))
command_full_number.append(ord(lbyteChar))
command_full_number.append(0x03)

print("whole command:",command_full)

ser = serial.Serial('/dev/tty.usbserial',baudrate=38400)
enq_array = bytearray([ENQ])
ser.write(enq_array)
time.sleep(0.001)
command_array= bytearray(command_full_number)
ser.write(command_array)
time.sleep(0.010)
eot_array = bytearray([EOT])
ser.write(eot_array)

使い方

./send.py "0EPH  CH001P1010"