AnsweredAssumed Answered

PN7462 long HSUART input stream handling with hardware flow control

Question asked by Gaurang K on Mar 13, 2020
Latest reply on Jun 22, 2020 by Gaurang K

Hi,

 

We are using PN7462C EVK for testing purposes. We want to develop a use case where any length of the HIF HSU input stream can be handled in PN7462 firmware. As per our current HIF HSU configuration, We can successfully handle the HIF HSU input stream less than 250 Bytes(Less than HIF HSU receive buffer size). But We can not able to receive whole data when input stream is more than 250 bytes. As per our understanding, this scenario must be handled by hardware flow control. I have referred to https://www.nxp.com/docs/en/user-guide/UM10858.pdf  and found that on Page #277 below note,

Note that in case the host sends a frame longer than the buffer size, a buffer_overflow interrupt will be sent to the firmware. The RTS will not toggle to high. Data received after the error are not stored into memory. The error is signaled to the firmware by an interrupt.

 

Below is some scenario we have thought and tried along with issues we are facing in the scenario,

1. Handle buffer_overflow interrupt and toggle the RTS pin manually.

Que: We are unable to find a way to toggle the RTS pin from firmware. We may lose some data bytes in this scenario. 

 

How can we handle this scenario in PN7462 firmware?

 

Attached our HIF HSU configuration code snippets.

Attachments

Outcomes