Could you please mention the PSoC device you are using? I assume it is PSoC 5 LP.
Are you using the Mark/Space feature that differentiates between address or data?
Yes, PSoC 5lp. I don't use Mark/Space. Half duplex.
I musst somehow react to the 9th bit. If it is 1, then it comes from a master device and is a request and I need to further check the message.
If it is a 0, then it comes from slave devices and I can ignore it.
Now depend on adjustments, it can be also the stop bit. If there is no stop bit, then it would lead in a framing error.