> I was not aware of the limitation of TFIS only working for RX -> TX. Where is that documented?
There is "Figure 117: IFS timing detail" in the NRF52840 manual which shows only RX->TX and I followed this. I don't see any description of how RADIO behaves on TX->RX when TIFS is enabled. So we probably need to verify this feature on HW. sob., 18 lip 2020 o 17:39 Matias N. <mat...@imap.cc> napisał(a): > > > TIMER capture + PPI enables you to get exact times of radio events. > Without > > this you probably cannot handle TIFS or window widening properly. > > There is hardware support for TFIS but it is usable only for RX -> TX > > transition. For TX -> RX you have to use TIMER capture to know how long > > you should wait in RX state. > > I was not aware of the limitation of TFIS only working for RX -> TX. Where > is that documented? > On nRF52832 PS I see: > > TIFS is only enforced if END_DISABLE and DISABLED_TXEN or END_DISABLE and > DISABLED_RXEN > shortcuts are enabled. TIFS is only qualified for use in BLE_1MBIT mode, > and default ramp-up mode. > > Which would seem to work for for both TX and RX. Anyway, I understand now > there may be some subtle > timings I have not yet encountered for which TIMER may be needed. > In any case, I see now that TIMER/RTC can be interlinked with RADIO via > PPI so that appears the way to go. > > > > I looked a bit at Zephyr's stack, and in the process found this video > > which cleared some questions about the code (which is quite complex): > > https://www.youtube.com/watch?v=rIicvcriWR8 > > > > The code in Zephyr is complex and completely unreadable :) > > Yes, I was a bit shocked when looking at the code from inside.
