The main purpose of this new COM implementation is that it is
much simpler, and requires less code space. This takes a bit
of the pressure off of the CC bootloader which was right at
the limit of available code space in the bootloader partition.
This is not intended to ever be used by the application.
This driver also formalizes the assumptions in the bootloader's
usage of the COM layer. All messages are assumed to arrive
in atomic chunks from the HID layer.
These files do not contain content from the ID in the header.
This name seems to have been cut/pasted all over throughout
the openpilot source tree and should be removed from any files
that should not rightfully be attributed to this person.
The PIOS_COM_ReceiveBufferUsed() function call is no longer
necessary since the same semantics can be achieved using calls
to PIOS_COM_ReceiveBuffer().
Summary of changes:
* USB CDC and HID drivers are completely split apart.
* This will allow different max buffer sizes for HID and CDC.
* USB descriptors have been overhauled:
* Proper structs/macros/enums declared for USB (see pios_usb_defs.h)
* Two common descriptor definitions. One for HID+CDC another for HID only.
See pios_usb_desc_{hid_cdc,hid_only}.c for details.
* Long standing bugs in OP USB descriptors became much more obvious with the
new struct definitions.
* Board specific USB initialization is now in pios_usb_board_data.h in each build target.
* Definition of USB descriptors is now entirely indpendent of STM32 libs.
Glue into STM32 libs is provided by pios_usbhook.c.
* Removed a lot of stale/irrelevant USB #defines throughout the tree.
* Improved naming consistency throughout USB code:
* PIOS_USB_HID_* now refers to the HID endpoint code.
* PIOS_USB_CDC_* now refers to the CDC endpoint code.
* PIOS_USB_* now refers to the low-level USB code.
* PIOS_USB_BOARD_* now refers to board-specific USB data
* PIOS_USBHOOK_* is glue between PIOS and STM32 USB libs.
* struct usb_* and enum usb_* and USB_* and HID_* are all types from the USB spec.
* Shrunk the buffer size on the CDC call mgmt endpoint to save some RAM.
* Made a few more USB related variables static to save some RAM.
Not all transmitters will continue to run when disconnected.
USB is one example of this. When the USB cable was disconnected,
any transmitter blocked here would wait forever.
This was particularly noticeable when the telemetry Tx task
blocked forever on USB disconnect. This also resulted in
the telemetry Rx task blocking forever waiting on the UAVTalk
connection lock.
We now block for a max of 5s waiting for space in the transmit
buffer.
PIOS_COM_SendBufferNonBlocking() will now fragment its buffer
to match the max size of the underlying device.
This allows the buffer size of the underlying device to shrink
below the maximum message size, thus allowing us to use smaller
buffers on memory-constrained platforms.
Reduced scope of many variables since they were being
exposed unnecessarily.
Renamed pios_usb_hid_prop code to pios_usbhook to reflect
the fact that it implements all of the callout functions
that are hooked into the stm32 usb library.
No code changes, just file, variable and define names are changed.
First, it better describes the serial protocol used by DSMx satellite
receivers. Second, many people using Spektrum radio, assume Spektrum
protocol. This is the attempt to address those inaccuracies.
- both CC serial ports are now disabled by default (no telemetry);
- serial ports now have DSM2, DSMX (10bit) and DSMX (11bit) options;
- ReceiverGroups now have DSM (MainPort) and DSM (FlexiPort) options.
For DSM2 protocol there is an explicit resolution bit in the stream, so
the DSM2 should be selected. For DSMX there is no such bit, and user
should choose the resolution from the list configuring the spektrum port.
ReceiverGroups have single DSM option which is handled by the same driver.
Downside: this implementation saves received frame first, unrolls by the
end of frame. This should be ok, but may be improved by unrolling channels
on the fly in the rx callback.
Another minor difference is that a ChannelGroup is now bound to port:
DSM (MainPort) or DSM (FlexiPort). This was considered as acceptable
solution in order to not have 6 DSM options for each ChannelGroup and
even more in case of new DSM protocol variations.
Known problem: it is not possible to choose same protocols like
DSM2/DSM2 for two ports. It can be enabled by adding an exception to
common rule, though.
The DSMX throttle channel misbehavior (zero value) is not treated
specially yet. It should trigger the failsafe being out of bounds.
More info and data dumps are required to handle this properly.
In the previous version the decoder could in rare cases get synced from
the middle of data stream in case of data byte equal to the S.Bus start
of frame (SOF) byte (wrong data will be rejected but it was not perfect).
Now it waits for the real start of frame and then checks the SOF byte.
- does not glitch when used in 2-frame mode (DM9, 9503, etc)
- does NOT provides yet DSMX stream decoding - do NOT merge
- uses a bit more time in the interrupt, but frees 16 bytes of RAM.
This is done to help decoding the weird DSMX stream which does not
contain explicit resolution/frame/lost frames info and needs special
processing (to be done yet).
TIM5-8. Also TIM1 was not handled probably (for CC either) as the name of the
IRQ is TIM1_CC and TIM1_UP for the capture compare versus update. I haven't
checked the downstream code that the registers it uses to map from a context to
event is invariant under timer channel.
