Data Sent through module is converted incorrectly

Question

I’m using the WIZ750SR-100. All my connections have been correctly established using the datasheet. I’m using it to convert ethernet data into serial data and vice versa. I expect to send a byte and receive that same byte on the other side of the conversion. This is not happening. For example, I send over UDP byte 01, and read on the serial side bytes: 7F 00. Also, I send UDP byte 19, and read on the serial side byte 73. This is all very reproducible, and every byte value I send I could map to a random byte value it is converting. This conversion works both ways, if I send byte 01 from serial to ethernet I get 7F 00 on the ethernet side, if I send byte 01 on the ethernet side I get 7F on the serial side without the extra 00. I’ve confirmed that the wiz module is converting incorrectly by monitoring both the input serial signal and input ethernet signal using oscilloscope to confirm that I am sending the correct data into the device. Also I’ve monitored the stream using wireshark and the serial using a separate rs232 monitor. I’ve confirmed this issue with 2 wiz devices. Maybe I’ve done something wrong in my setup, or misunderstand how this device works. Any thoughts? EDIT I am using the correct bauds on all devices, I’ve confirmed this with scope monitoring

rmc · Answer

Found the issue, device datasheet uses RS-232, TTL, and LVTTL interchangeably. The true level is LVTTL.