Besides of knob PID tuning it is now possible to use throttle channel
to ramp-shape PID coefficients. This can be used to lower some PIDs on
VTOL while sinking to prevent wobble.
To use the feature select throttle as control input, choose throttle
range max and min values, assign the instance to particular PID
coefficient and define a range for it. When throttle is lower than
defined throttle range min value (or higher than max), then min and max
PID values will be used accordingly. Changing throttle from throttle
min to max will linearly scale PID value.
Note that it is possible to set MinPID > MaxPID. In that case increasing
control input value will decrease the PID coefficient.
Up to 3 independent instances can be configured. The number can be
increased changing the UAVO definition, but at the cost of extra RAM.
This module will periodically update values of stabilization PID settings
depending on configured input control channels. New values of stabilization
settings are not saved to flash, but updated in RAM. It is expected that the
module will be enabled only for tuning. When desired values are found, they
can be read via GCS and saved permanently. Then this module should be
disabled again.
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.
them symbolic constants.
- A timeout is 0
- A missing driver is 65534
- An invalid channel is 65535
ManualControl: Make it deal with the values explicitly. A timed out value
should not be treated like a minimum duration signal. Instead it does not
updated the scaled value but marks the data window as invalid to trigger the
failsafe.
Allocate per-instance data for drivers from the heap
rather than as static variables from the .data segment.
This converts > 800 bytes of RAM from being always consumed
as static data into being allocated from the heap only when
a particular feature is enabled in the hwsettings object.
A minimal config (no receivers, flexi port disabled, main port
disabled) leaves 2448 bytes of free heap. That's our new baseline.
Approximate RAM (heap) costs of enabling various features:
+ 632 Serial Telemetry (includes 400 bytes of Rx/Tx buffers)
+ 108 PWM Rcvr
+ 152 PPM Rcvr
+ 112 Spektrum Rcvr
+ 24 S.Bus (Should be closer to 68 since driver is still using
static memory)
There are still some drivers that pre-allocate all of their memory
as static data. It'll take some work to convert those over to
dynamically allocating their instance data.
PWM and PPM can now coexist in the same load and be
selected at boot time via the hwsettings UAVObject.
This is basically a complete restructuring of the
way the drivers interact with the TIM peripheral in
the STM32.
As a side effect, the PWM and PPM drivers are now
ready to support multiple instances of each.
This also provides the first step toward being able
to reassign some of the PWM input pins to be servo
output pins. Still more work required, but this is
a good start.
