PSoc1 - RX8 -> generate of a false interrupt if you going from dissable to enable interrupt. High Input on RX data, no data on this moment . What is the reason?

[SampathS_11]

Hello @LuSa_1231216 ,

After enabling and servicing the interrupt, maintain RX_IN high. Then disable the interrupt, and enable it again. Let me know if you see and interrupt being generated again. Read the INT_CLRx registers to see if the interrupt is active before it is disabled.

Best regards,

Sampath

[LuSa_1231216]

The problem is always the same, i take a snapshot ->  yellow is the RX in Data signal and blue is the RX8 interrupt , the peak interrupt is after +/- 250µs and RX8 enable and rising edge. If i take  longer times  to disable and enable  = longer time positive Rx signal,  but the same result .

[SampathS_11 · Accepted solution]

Hello @LuSa_1231216 ,

I suppose this issue is related to PSoC1, RS485 transceiver High Z Ro output (when enable is high, see table), does have anyone a solut...

Does adding an external pull-up to MAX485-RO resolve this issue? The Rx /P1[6] going low and come back high again is recognized as a stop bit, and the interrupt is generated internally. It is pending till you enable interrupts in the UART User Module.

You can try one of two things:

• Set the initial value of P1[6] to 1 
• Connect P1[6] to another free GPIO, configured as Resistive Pull Up.

Best regards,

Sampath Selvaraj