ESP8266 Community Forum

- Sat May 16, 2015 2:15 am #17528 I did use the term oldfashioned within quotes!

But the technique really is oldfashioned, I have never bought devices with RS232C connectors for over ten years (although they are available). There is really no sane reasoning to still use it.

Anyway with esp8266 + level shifter you can make those devices "wireless".

- Sat May 16, 2015 3:14 am #17529

Great stuff thanks!
I have it working fine when I test it with socket test, but I would really like to make it work bi-directionally...if that is correct?
I would like to use this to replace a serial connection with comms both ways, possibly by using a VCP (virtual comm port) driver or software.
Would this require an additional MCU or similar to handle the server/client stuff or am I missing something.

It *is* a transparent bridge, with serial comms in both directions between the comuter and an MCU or similar, connected to the Rx/Tx Lines of the ESP.

Thanks ArnieO
I wonder what I am doing wrong?
I can only seem to send to the ESP via TCP. This "comes out" the UART 100%
When I try to send back the other way, nothing.
To clarify, I am using a VCP (virtual comm port) program to create a virtual port (com10) via TCP (port 23) to the ESP.
This works, and it shows the flow of data on it's status scren.
I have 1 terminal "connected" to com10
I have another terminal connected to com4 (ESP UART) which is the port I flash the ESP with.
Both ports on the same computer.
Talking to this ESP via com4 works 100% for telnet, flashing, AT commands etc.
When I send chars from the vcp terminal (com10) they show on the VCP program and "appear" at com4 terminal via ESP UART.
When I enter chars at com4 term (ESP UART) they do not show at com10 or on the VCP status page.
It seems to me they do not know where to go?
I am connected to the ESP (which is in Mode 3) via its standard AP SSID directly from my pc not via a network or router.

I apologise if this is mind numbing for you, but I have so many legacy (and new) serial devices (most TTL, NOT RS232) that would benefit from this.

Thanks in advance for any comments, I suspect the issue is that I know a little but not quite enough.
BTW, this is my first exposure to Flashing firmware etc, so it is all a bit of a learning curve.

The purpose of this firmware is that the ESP replaces USB cable / UART so that you can communicate wirelessly with for instance an Arduino. In such a setup, the ESP Rx/Tx are connected to Arduino Tx/Rx. The UART is not used. When set up properly you can for instance program the Arduino wirelessly, or monitor it wirelessly.
In your setup you seem to have a UART connected to the ESP Rx/Tx, which leaves me wondering what you are attempting to accomplish?

- Sat May 16, 2015 3:26 am #17532

I did use the term oldfashioned within quotes!

But the technique really is oldfashioned, I have never bought devices with RS232C connectors for over ten years (although they are available). There is really no sane reasoning to still use it.

Anyway with esp8266 + level shifter you can make those devices "wireless".

You are correct of course, it is old fashioned. That is why I wonder why (some) big name new radios are only equipped with TTL level comms. You can of course buy a USB to radio "programming lead" or build one, which is what most hams do.
I am trying to avoid either removing the radio from the car, taking a laptop to the car, or running a long cable to the car every time I want to reprogram the radio's memory channels.

- Sat May 16, 2015 3:37 am #17535

The purpose of this firmware is that the ESP replaces USB cable / UART so that you can communicate wirelessly with for instance an Arduino. In such a setup, the ESP Rx/Tx are connected to Arduino Tx/Rx. The UART is not used. When set up properly you can for instance program the Arduino wirelessly, or monitor it wirelessly.
In your setup you seem to have a UART connected to the ESP Rx/Tx, which leaves me wondering what you are attempting to accomplish?

Thanks again for persisting..
The UART connection to the ESP now is for testing only.
When/if I get my head around this, it will work exactly as you describe, but instead of programming or monitoring an Arduino , it will be my radio (amateur radio), so I can program it without removing it from my car, or having to use a laptop etc.
I still am only getting one way comms (from VCP to ESP) the response from the terminal connected to the ESP tx/rx does not go back to the terminal running connected to the virtual com port.
I must use VCP software since I must use Radio "programming" software that can only connect to the radio via an RS232 or USB port.