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nRF905 timing requirements when auto-retransmitting.

Hi,

We are using the nRF905 device in an application where it needs to switch between auto-retransmitting and sending single packets, due to it communicating with several types of devices. To simplify the software design, we would like to not reconfigure the radio, but leave the AUTO_RETRAN flag high at all times.

When transmitting with the AUTO_RETRAN flag unset, we would wait for DR to be set high, and set TX_EN, TRX_CE and PWR_UP low immediately. This works just fine.

However, when the AUTO_RETRAN flag is set, it seems the data is not received unless the transceiver is kept on for a short time after the DR signal is set high (the first time it happens, as we want to send only a single packet). We still set TX_EN low as soon as we get the DR.

Are there any timing requirements regarding this that we are unaware of? Will setting TRX_CE low before getting a high DR allow us to turn off the radio immediately?

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