HiLetgo 5pcs RS232 to TTL Converter Module COM Serial Port Board MAX3232 MAX232CSE

It worked as documented and desired. What more could I want?

The media could not be loaded. So, I used this TTL to connect my scale with a RS232 output. Then connected to Arduino Nano for the logic functions of reading the scale info and then only printing the weight value from the scale in numeric and barcode format. It’s a dedicated solution I was targeting for and succeeded. After finalizing the code and electronic connections I then 3d printed a case to enclose all components. Turned out really nice. The printer uses the hardware serial rx and rx while the scale uses software serial1 for the scale rx and rx.

I saw some reports that TX & RX were labelled incorrectly in the reviews. This is also the case with all of the units I received. Labels on the board have TX/RX pins reversed. Removed one star for that, but they otherwise work great.

I saw reviews that said the PCB was marked incorrectly, that the chip was a MAX232 instead of a MAX3232 and the chip overheated. I did not see any of these issues. All 5 of my boards had MAX3232 chips installed, were marked correctly and ran cool. Note that the "schematic" shown (also attached) is completely wrong. GND of the CPU is shown connected to RXD, CPU TXD is connected to GND and CPU RXD is connected to TXD. The correct connection is CPU GND to GND (obviously), CPU TXD to TXD and CPU RXD to RXD.I connected the board to a TI MSP430F5338 and it works fine at 115.2K when connected to my PC. I would have preferred that the 4 pin connector was ship separately as I used wires to connect the board, but I just wired to the back of the board. Not mentioned in the documentation is a red LED power indicator.

Great product for the money. Mine were all RS3232 chips and output correct voltage. Unfortunately, the pin labled txd is actually rxd and rxd is txd. A lame mistake by the maufacturer but once you know, they work well. Using this for serial testing with a LibreComputer "Le Potato" connected to pins 4,6,8,10 which map to /dev/ttyAML6 once you "ldto enable uarta". I would buy more but this came with 5x units. All set for four more projects.

I was using this to convert the TTL from the Arduino to the RS232 of my Stone HMI display. Then I got brave and removed the 4 SMT resistors on the Display and re-soldered them on the TTL line. Now I don't need these, but they were very good for testing functionality before doing surface mount soldering...

These do NOT work with 3.3V VCC as the MAX3232 spec indicates they should. They only work with 5V VCC. Do not use with Raspberry Pi 3.3V UART, as the 5V VCC results in an overvoltage on the 3.3V UART pins.

I use these in my PIC projects.