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Jorge Aparicio 2020-07-14 12:08:44 +02:00
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6
embedded-workshop-book/src/advanced-next-steps.md
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@ -5,7 +5,7 @@
If you'd like to continue working on your workshop project, we recommend adding String Descriptors support to the USB firmware.
- First, you'll want to read through section 9.6.7 of the USB spec, which covers string descriptors.
- Next, we suggest you change your *configuration* descriptor to use string descriptors. You'll want to change the `iConfiguration` field to a non-zero value.
- Next, we suggest you change your *configuration* descriptor to use string descriptors. You'll want to change the `iConfiguration` field to a non-zero value. Note that this change will likely break enumeration.
- Now, re-run the program to see what new control requests you get from the host.
- You'll need to update the `usb` parser to handle the new requests.
- Then you can extend the logic of `ep0setup` to handle these new requests.
@ -16,7 +16,7 @@ To verify that string descriptors are working in a cross-platform way you can ex
[`read_string_descriptor`]: https://docs.rs/rusb/0.6.2/rusb/struct.DeviceHandle.html#method.read_string_descriptor
## RTIC
## Explore more RTIC features
We have covered only a few of the core features of the RTIC framework but the framework has many more features like *software* tasks, tasks that can be spawned by the software; message passing between tasks; and task scheduling, which allows the creation of periodic tasks. We encourage to check the [RTIC book][rtic-book] which describes the features we haven't covered here.
@ -24,7 +24,7 @@ We have covered only a few of the core features of the RTIC framework but the fr
## usb-device
[`usb-device`] is a library for building USB devices. It has been built using traits (the pillar of Rust's *generics*) such that USB interfaces like HID and TTY ACM can be implemented in a device agnostic manner. The device details then are limited to a trait *implementation*. There's a work in progress implementation of the `usb-device` trait for the nRF52840 device in [this PR] and there are many `usb-device` "classes" like [HID] and [TTY ACM] that can be used with that trait implementation.
[`usb-device`] is a library for building USB devices. It has been built using traits (the pillar of Rust's *generics*) such that USB interfaces like HID and TTY ACM can be implemented in a device agnostic manner. The device details then are limited to a trait *implementation*. There's a work in progress implementation of the `usb-device` trait for the nRF52840 device in [this PR] and there are many `usb-device` "classes" like [HID] and [TTY ACM] that can be used with that trait implementation. We encourage you to check out that implementation, test it on different OSes and report issues, or contribute fixes, to the `usb-device` ecosystem.
[this PR]: https://github.com/nrf-rs/nrf-hal/pull/144
[HID]: https://crates.io/crates/usbd-hid

3
embedded-workshop-book/src/beginner-next-steps.md
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@ -15,9 +15,10 @@ The `Radio` abstraction supports 2 CCA modes: `CarrierSense` and `EnergyDetectio
Here are some things for you to try out:
- First, read the section 6.20.12.4 of the nRF52840 Product Specification, which covers the nRF52840's implementation of CCA.
- Disconnect the Dongle. Write a program for the DK that scans and reports the energy levels of all valid 802.15.4 channels. In your location which channels have high energy levels when there's no ongoing 802.15.4 traffic? If you can, use an application like [WiFi Analyzer] to see which WiFi channels are in use in your location. Compare the output of WiFiAnalyzer to the values you got from `energy_detection_scan`. Is there a correspondence? (Note that WiFi channels don't match in frequency with 802.15.4 channels; some mapping is required to convert between them)
- Disconnect the Dongle. Write a program for the DK that scans and reports the energy levels of all valid 802.15.4 channels. In your location which channels have high energy levels when there's no ongoing 802.15.4 traffic? If you can, use an application like [WiFi Analyzer] to see which WiFi channels are in use in your location. Compare the output of WiFiAnalyzer to the values you got from `energy_detection_scan`. Is there a correspondence? Note that WiFi channels don't match in frequency with 802.15.4 channels; some mapping is required to convert between them -- check [this resource] for more details about co-existence between 802.15.4 and WiFi.
[WiFi Analyzer]: https://play.google.com/store/apps/details?id=com.farproc.wifi.analyzer&hl=en
[this resource]: https://inet.omnetpp.org/docs/showcases/wireless/coexistence/doc/
- Choose the channel with the highest idle energy. Now write a program on the DK that sets the CCA mode to `EnergyDetection` and then send a packet over this channel using `try_send`. The `EnergyDetection` CCA mode requires a Energy Detection (ED) "threshold" value. Try different threshold values. What threshold value makes the `try_send` succeed?