Continuing the discussion from Software serial reading 1 byte:
Hello,
I want to send many commands through RS-232 to an aircraft display unit. Rx, Tx signal to send/receive have the amplitude -6V to +6V. As the manual of this display unit, the commands to send have the type as: "360 0 2", "610 0 1E", "510 0 1F", "503 0 EEEE",... for maintenance or reset hardware.
Can you give me some advices how to send, configure, perform,... this commands through RS-232 port ?
Thank you,
V5D
Do you have the RS-232 adapter board?
Everything you need to know about serial is here
https://docs.arduino.cc/language-reference/en/functions/communication/serial/
You will also need a TTL to RS232 adaptor.
Yes, I use Excalibur M4KSerialPlus2 to send these commands...
To send these commands I have use the free software SerialSimulationLabs (SSL) using with excel file to configure each command before sending...
Then what problem do you have?
I don't know how to configure the number in these commands, for example in "503 0 1E", is the 503 number decimal or octal, hexadecimal,...
How do you interpret this commands if the manual doesn't explain ?
We can configure the number in these commands as:
I look at your example! I see spaces. Those are neither numeric nor hex. Therefor the only possible interpretation of your example is they are simply ASCII characters. With spaces being a valid ASCII character.
It's not bad the way you interpreted the command but it doesn't work for my application.
Thanks for replaying
Could I use an Arduino UART (Tx, Rx pins) to send directly a command mentioned ("503 0 1E" for example) to this aircraft device ?
Perhaps the Baud rate does not match your display unit.
I thought you determined the serial communications was RS-232?
Can you share the manual you are using so we can see what the manual says.
Would that be Excalibur Systems (mil-1553.com)? I'm guessing you are referring to this board: https://www.mil-1553.com/m4kserialplus.
You cannot directly connect the Arduino UART Rx & Tx pins as they do not provide the voltages required by RS-232. You will need an adapter as @jim-p mentioned in post #3.
No.
They are 5V I/O.
+/-6V will damage the Arduino
The manual doesn't say much, they just tell the information for RS232 and asking to send the commands to the device through RS232.
Here is this:
YES, M4KSerialPlus2 (for 2 channels: 0&1)
Ok. That's the basic UART frame format information. What about the format of the actual messages you need to send to the display?
By the way, is this the display you are trying to talk to:
The outputs Tx signal amplitude of this M4KSerialPlus is ±6V. This signal connected to input (pin #13, R1IN) of IC MAX232 (Vcc = 5V). The output is at pin #12, R1OUT) that has an amplitude around +4V to send to a CPU (I guess). That Why I'm thinking If I can use an Arduino to send and read data from CPU of device bypassing the RS232 IC and adaptor board M4KSerialPlus.
Do you think it's possible ?
YES, SMD68 display
Please refer to post #1. Thanks
