Losing Messages between sender and receiver over serial line

[beadon]

Messages sent from the nRF52832 over serial, using nrf_serial seem to be getting lost periodically as they are received via an implementation on an Android Tablet.  We are stumped as to why data is being lost consistently when the nRF52832 is accesses over one particular line of the FTDI USB-to-4xUART chips ( FT4232HL ).  We are using SDK 14.2.

We have observed the issue as a CRC mismatch on the packets, after about the first 10 to 50 packets of the data file are transferred. Each packet is ~1000 Bytes, and a data file consists of ~36000 packets. This issue only occurs down one of the ports.

Has anyone seen this before ?  Can we mitigate the issue in some way to ensure that transfers progress properly ?

[Susheel Nuguru]

Interesting, So only the port where nRF52 is connected is loosing packets and rest of the ports are working without data loss?

Is nRF52 chip configured to work with the serial with flow control enabled? What is the baudrate you are using? 

Looking at the spec of FT4232H (page 11), there seems to be a way to configure the pull of the serial pins, please check if this configuration is not contradicting the pin pulls from the nrf side.