RS232

Projects General Guidance
1

May a dum question :confused: : Can I send the serial signals to a device I found. This are the codes : LINK
I am not sure about how to send all data in once through SOFTSERIAL. Is it just one after the other?
May some tiny tiny line of codes would give me a starter?

Thanks in advance

2

You want us to open an Excel spreadsheet. WHY ?

3

Just to see what the spec is requesting in regards to the data. Here is a copy of some data:

RS-232 Control Commands
MODEL HD41-ARC

RS-232 protocol
Baud Rate 9600
Data Bits 8
Parity Check none
Stop Bits 1
Flow control none

Basic controls
Note: The commands are in HEX. No spaces between HEX codes.

HEX CODE
Port Status 0x02 0x30 0x30 0x31 0x03
Turn ON LED 0x02 0x30 0x30 0x33 0x03
Turn OFF LED 0x02 0x30 0x30 0x34 0x03
Turn ON Power 0x02 0x30 0x30 0x35 0x03
Turn OFF Power 0x02 0x30 0x30 0x36 0x03
Turn ON Smart Scan 0x02 0x30 0x30 0x37 0x03
Turn OFF Smart Scan 0x02 0x30 0x30 0x38 0x03

4

soulid:
May a dum question :confused: : Can I send the serial signals to a device I found. This are the codes : LINK
I am not sure about how to send all data in once through SOFTSERIAL. Is it just one after the other?
May some tiny tiny line of codes would give me a starter?

Thanks in advance

No problem, but, you need a RS232 Level converter, The Serial output of the Arduino is TTL(0..5V) not (12..-12V) of RS232.

void ledOn(){
Serial.write(0x02);
Serial.write(0x30);
Serial.write(0x30);
Serial.write(0x33);
Serial.write(0x03);
}

Chuck.

5

"you need a RS232 Level converter,..."

Maybe not. Lots of 'RS232' these days is OK with 0/5V. With softwareserial, use Inverted.
If it's supposed to take data back from the device, there ought to be 20k in series, in case it is using +/-12V, taking advantage of the 328's I/O pin internal diode network.

6

if it is actually RS232, from +3 to -3 is hysteresis. +5v could be identified as deAsserted, but you would never have any Asserted signal level. I have never seen any RS232 chips that allow 0v to be the Asserted signal level. Do you know the partnumbers for these 'special' RS232 IC's?

Chuck.

7

No IC, what they do is limit the +12V with e.g. a zener and short (or block, not sure) the -12 with a diode; that limits the voltages so they are safe for the micro.

8

sterretje:
No IC, what they do is limit the +12V with e.g. a zener and short (or block, not sure) the -12 with a diode; that limits the voltages so they are safe for the micro.

So you are talking input to Arduino, NOT output of RS232 signals.

I can agree that using a current limit resistor on the RX pin will allow the Arduino to receive from a Strong RS232 signal, but it will not have any hysteresis or noise immunity.

It will not be able to SEND RS232 signals.

Chuck.

9

I'm aware that it's officially not RS232.

I had this Elektor 8032 board long ago and it happily hooked to a RS232 port on a 386 PC and worked; only tested on shorter distances though.