Support scaling the ilimit on a per-command basis

This makes it possible to switch between velocity and position mode
when a non-zero ilimit is configured.

docs/reference.md

@@ -897,41 +897,49 @@ If specified and not-NaN, then the control mode will temporarily be in
 the "fixed voltage" mode, regardless of the current setting of
 `servo.fixed_voltage_mode`.
 
-### 0x030 - Proportional torque ###
+#### 0x02b - Ki ilimit scale ####
+
+Mode: Read/write
+
+When in Position mode, shrink the integral term's windup limit by the
+given factor.  Integral types are applied as for PWM.  If unspecified,
+1.0 is used.
+
+#### 0x030 - Proportional torque ####
 
 Mode: Read
 
 This reports the torque contribution from the proportional term in the
 PID controller.
 
-### 0x031 - Integral torque ###
+#### 0x031 - Integral torque ####
 
 Mode: Read
 
 This reports the torque contribution from the integral term in the
 PID controller.
 
-### 0x032 - Derivative torque ###
+#### 0x032 - Derivative torque ####
 
 Mode: Read
 
 This reports the torque contribution from the derivative term in the
 PID controller.
 
-### 0x033 - Feedforward torque ###
+#### 0x033 - Feedforward torque ####
 
 Mode: Read
 
 This reports the feedforward contribution in the PID controller.
 
-### 0x034 - Total control torque ###
+#### 0x034 - Total control torque ####
 
 Mode: Read
 
 This reports the total commanded torque from the position mode
 controller.  This is also reported in 0x03a.
 
-### 0x038 - Control Position ###
+#### 0x038 - Control Position ####
 
 Mode: Read
 
@@ -940,7 +948,7 @@ that is valid.  When velocity or acceleration limiting is enabled, the
 control position will follow the desired limits to achieve the command
 position.
 
-### 0x039 - Control Velocity ###
+#### 0x039 - Control Velocity ####
 
 Mode: Read
 
@@ -949,32 +957,32 @@ is valid.  When velocity or acceleration limiting is enabled, the
 control velocity will follow the desired limits to achieve the control
 position and velocity.
 
-### 0x03a - Control Torque ###
+#### 0x03a - Control Torque ####
 
 Mode: Read
 
 The torque commanded by the control loop.  This is the same as 0x034.
 
-### 0x03b - Position Error ###
+#### 0x03b - Position Error ####
 
 Mode: Read
 
 The current sensed position minus the control position.
 
-### 0x03c - Velocity Error ###
+#### 0x03c - Velocity Error ####
 
 Mode: Read
 
 The current sensed velocity minus the control velocity.
 
-### 0x03d - Torque Error ###
+#### 0x03d - Torque Error ####
 
 Mode: Read
 
 The current sensed torque minus the control torque.
 
 
-### 0x040 - Stay within lower bound ###
+#### 0x040 - Stay within lower bound ####
 
 Mode: Read/write
 
@@ -986,7 +994,7 @@ feedforward torque is applied.  When outside this bound, the PID
 controller is used to force the position back to the bound.  If
 unspecified, 0.0 is used.
 
-### 0x041 - Stay within upper bound ###
+#### 0x041 - Stay within upper bound ####
 
 Mode: Read/write
 
@@ -998,108 +1006,112 @@ a feedforward torque is applied.  When outside this bound, the PID
 controller is used to force the position back to the bound.  If
 unspecified, 0.0 is used.
 
-### 0x042 - Feedforward torque ###
+#### 0x042 - Feedforward torque ####
 
 A shadow of the 0x022 register.
 
-### 0x043 - Kp scale ###
+#### 0x043 - Kp scale ####
 
 A shadow of the 0x023 register.
 
-### 0x044 - Kd scale ###
+#### 0x044 - Kd scale ####
 
 A shadow of the 0x024 register.
 
-### 0x045 - Maximum torque ###
+#### 0x045 - Maximum torque ####
 
 A shadow of the 0x025 register.
 
-### 0x046 - Watchdog timeout ###
+#### 0x046 - Watchdog timeout ####
 
 A shadow of the 0x027 register.
 
-### 0x050 - Encoder 0 Position ###
+#### 0x047 - Ki ilimit scale ####
+
+A shadow of the 0x02b register.
+
+#### 0x050 - Encoder 0 Position ####
 
 Mode: Read only
 
 Reports the current filtered position of the encoder configured in
 slot 0.
 
-### 0x051 - Encoder 0 Velocity ###
+#### 0x051 - Encoder 0 Velocity ####
 
 Mode: Read only
 
 Reports the current filtered velocity of the encoder configured in
 slot 0.
 
-### 0x052 - Encoder 1 Position ###
+#### 0x052 - Encoder 1 Position ####
 
 Mode: Read only
 
 Reports the current filtered position of the encoder configured in
 slot 1.
 
-### 0x053 - Encoder 1 Velocity ###
+#### 0x053 - Encoder 1 Velocity ####
 
 Mode: Read only
 
 Reports the current filtered velocity of the encoder configured in
 slot 1.
 
-### 0x054 - Encoder 2 Position ###
+#### 0x054 - Encoder 2 Position ####
 
 Mode: Read only
 
 Reports the current filtered position of the encoder configured in
 slot 2.
 
-### 0x055 - Encoder 2 Velocity ###
+#### 0x055 - Encoder 2 Velocity ####
 
 Mode: Read only
 
 Reports the current filtered velocity of the encoder configured in
 slot 2.
 
-### 0x058 - Encoder Validity ###
+#### 0x058 - Encoder Validity ####
 
 Mode: Read only
 
 Returns a bitfield, where bit 0 indicates whether encoder 0 is active,
 bit 1 indicates whether encoder 1 is active, etc.
 
-### 0x05c - Aux1 GPIO Command ###
+#### 0x05c - Aux1 GPIO Command ####
 
 Mode: Read/write
 
 The current output command for any GPIOs configured as an output on
 aux1 as a bitfield.  Not all bits may be used, as bit 0 is always for
 pin 1, whether or not it is configured as a GPIO output.
 
-### 0x05d - Aux2 GPIO Command ###
+#### 0x05d - Aux2 GPIO Command ####
 
 Mode: Read/write
 
 The current output command for any GPIOs configured as an output on
 aux2 as a bitfield.  Not all bits may be used, as bit 0 is always for
 pin 1, whether or not it is configured as a GPIO output.
 
-### 0x05e - Aux1 GPIO Status ###
+#### 0x05e - Aux1 GPIO Status ####
 
 Mode: Read only
 
 The current input value of any GPIOs configured as an input on aux1 as
 a bitfield.  Not all bits may be used, as bit 0 is always for pin 1,
 whether or not it is configured as a GPIO input.
 
-### 0x05f - Aux2 GPIO Status ###
+#### 0x05f - Aux2 GPIO Status ####
 
 Mode: Read only
 
 The current input value of any GPIOs configured as an input on aux2 as
 a bitfield.  Not all bits may be used, as bit 0 is always for pin 1,
 whether or not it is configured as a GPIO input.
 
-### 0x060/0x064 - Aux1 Analog Inputs ###
+#### 0x060/0x064 - Aux1 Analog Inputs ####
 
 Mode: Read only
 
@@ -1108,7 +1120,7 @@ registers are associated with pins 1-5, regardless of whether they are
 configured as an analog input.  Each value is scaled as a PWM from 0
 to 1.
 
-### 0x068/0x06c - Aux2 Analog Inputs ###
+#### 0x068/0x06c - Aux2 Analog Inputs ####
 
 Mode: Read only
 
@@ -1117,15 +1129,15 @@ registers are associated with pins 1-5, regardless of whether they are
 configured as an analog input.  Each value is scaled as a PWM from 0
 to 1.
 
-### 0x070 - Millisecond Counter ###
+#### 0x070 - Millisecond Counter ####
 
 Mode: Read only
 
 Increments once per millisecond.  It wraps at the maximum value for
 the queried type to the minimum value for that type.  For floating
 point types, it counts integers from 0 to 8388608.
 
-### 0x071 - Clock Trim ###
+#### 0x071 - Clock Trim ####
 
 Mode: Read/write
 
@@ -1139,29 +1151,29 @@ microcontroller, including CAN communication.  Thus setting this to a
 non-zero value may prevent future CAN communications.
 
 
-### 0x100 - Model Number ###
+#### 0x100 - Model Number ####
 
 Name: Model Number
 Mode: Read only
 
 This returns a 32 bit model number.
 
-### 0x101 - Firmware Version ###
+#### 0x101 - Firmware Version ####
 
 Mode: Read only
 
 This returns a 32 bit firmware version, encoded bytewise as
 major.minor.micro.  i.e. 0x010304 is version 1.3.4
 
 
-### 0x102 - Register map version ###
+#### 0x102 - Register map version ####
 
 Mode: Read only
 
 This returns a number that indicates how to interpret all registers.
 
 
-### 0x110 - Multiplex ID ###
+#### 0x110 - Multiplex ID ####
 
 Name: Multiplex ID
 Mode: Configurable
@@ -1170,30 +1182,30 @@ This controls the primary ID used to access the device over the
 multiplex RS485 bus.  It can only be between 1 and 127.  (0 is
 reserved as the broadcast address).
 
-### 0x120 - 0x122 - Serial Number ###
+#### 0x120 - 0x122 - Serial Number ####
 
 Name: Serial Number
 Mode: Read only
 
 This returns a 96 bit serial number, least significant word first.
 
 
-### 0x130 - Set Output Nearest ###
+#### 0x130 - Set Output Nearest ####
 
 Mode: Write only
 
 When sent, this causes the servo to select a whole number of internal
 motor rotations so that the final position is as close to the given
 position as possible.
 
-### 0x131 - Set Output Exact ###
+#### 0x131 - Set Output Exact ####
 
 Mode: Write only
 
 When sent, the servo will force the output position to be the exact
 specified value.
 
-### 0x132 - Require Reindex ###
+#### 0x132 - Require Reindex ####
 
 Mode: Write only
 
@@ -1202,7 +1214,7 @@ position be re-located before control can begin.  Regardless, the
 position will reset to an arbitrary value consistent with the current
 encoder settings.
 
-### 0x133 - Recapture Position and Velocity ###
+#### 0x133 - Recapture Position and Velocity ####
 
 Mode: Write only
 
@@ -1214,7 +1226,7 @@ current applied torque is 0, either because of an in-place maximum
 torque limit of zero, or because of an in-place kp and kd scale of
 zero.
 
-### 0x140 - Driver Fault 1 ###
+#### 0x140 - Driver Fault 1 ####
 
 Mode: Read only
 
@@ -1223,7 +1235,7 @@ for fault register 1.  Up to 16 bits may be set.  This will only be
 non-zero if the current mode is fault (1) and the fault code is 33
 (motor driver fault).
 
-### 0x141 - Driver Fault 2 ###
+#### 0x141 - Driver Fault 2 ####
 
 Mode: Read only.
 
@@ -1347,6 +1359,8 @@ Each optional element consists of a prefix character followed by a value.  Permi
   constant for the duration of this command
 - `d` - kd scale: the configured kd value is multiplied by this
   constant for the duration of this command
+- `i` - ki ilimit scale: the configured ilimit value is multiplied by
+  this constant for the duration of this command
 - `s` - stop position: when a non-zero velocity is given, motion stops
   when the control position reaches this value.
 - `f` - feedforward torque in Nm

fw/bldc_servo.cc

@@ -1938,7 +1938,7 @@ class BldcServo::Impl {
     PID::ApplyOptions apply_options;
     apply_options.kp_scale = 0.0f;
     apply_options.kd_scale = data->kd_scale;
-    apply_options.ki_scale = 0.0f;
+    apply_options.ilimit_scale = 0.0f;
 
     ISR_DoPositionCommon(sin_cos, &zero_velocity,
                          apply_options, config_.timeout_max_torque_Nm,
@@ -1949,6 +1949,7 @@ class BldcServo::Impl {
     PID::ApplyOptions apply_options;
     apply_options.kp_scale = data->kp_scale;
     apply_options.kd_scale = data->kd_scale;
+    apply_options.ilimit_scale = data->ilimit_scale;
 
     ISR_DoPositionCommon(sin_cos, data, apply_options, data->max_torque_Nm,
                          data->feedforward_Nm, data->velocity);