Serial to old reciever. Problem with the serial comunication

Projects Programming
21

It is an AV reciever. The serial Communication/wiering is in the attached document

PuTTY on a PC with a USB to DB9 (9 pin) dongle + DB9 female to female between the pioneer and the USB dongle

PuTTY works without XON/XOFF with the USB dongle!

I used the com port that worked with Putty (USB dongle) in the serial monitor of the Arduino IDE, Then I only got the response E04 from the pioneer (in the serial monitor of Arduino IDE) - which according to the manual is "Command Error - Detects an inappropriate command line"

For the Arduino set-up I use a:
https://www.aliexpress.com/item/MAX3232-RS232-to-TTL-Serial-Port-Converter-Module-DB9-Connector-MAX232/32842352700.html?spm=2114.search0604.3.34.669755f3xBcrIc&ws_ab_test=searchweb0_0,searchweb201602_1_10152_10151_10065_10344_10068_10342_10343_5722611_10340_10341_10696_5722911_5722811_5722711_10084_10083_10618_10307_10820_10301_10821_10303_10059_100031_10103_10624_10623_10622_10621_10620_5722511,searchweb201603_11,ppcSwitch_5&algo_expid=27be6789-e454-484a-8afb-a89a6e8ea0e5-5&algo_pvid=27be6789-e454-484a-8afb-a89a6e8ea0e5&transAbTest=ae803_1&priceBeautifyAB=0

This card is connected to an Arduino Uno.

Is there some simple way for me to check if the connection/card is OK? can I connect the card to the USB dongle and use some simple test scetch?

Susano RS232.pdf (207 KB)