Implement mini sequencer

pure_adsr/mini_sequencer.h

@@ -0,0 +1,110 @@
+// Copyright 2013 Emilie Gillet.
+//
+// Author: Emilie Gillet (emilie.o.gillet@gmail.com)
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+//
+// See http://creativecommons.org/licenses/MIT/ for more information.
+//
+// -----------------------------------------------------------------------------
+//
+// Mini sequencer.
+
+#ifndef PEAKS_MODULATIONS_MINI_SEQUENCER_H_
+#define PEAKS_MODULATIONS_MINI_SEQUENCER_H_
+
+#include "pure_adsr/gate_processor.h"
+#include <stddef.h>
+
+#define abs(X) ((X) < 0 ? -(X) : (X))
+
+namespace pure_adsr {
+
+const uint8_t kMaxNumSteps = 4;
+
+class MiniSequencer {
+  public:
+  MiniSequencer() {}
+  ~MiniSequencer() {}
+
+  void Init()
+  {
+    for (size_t i = 0; i < kMaxNumSteps; i++)
+      steps_[i] = 0;
+    num_steps_ = 4;
+    step_ = 0;
+    reset_at_next_clock_ = false;
+  }
+
+  inline void set_step(uint8_t index, int16_t value)
+  {
+    int32_t difference = abs(int32_t(steps_[index]) - value);
+    if (difference > 0) {
+      steps_[index] = value;
+    }
+  }
+
+  inline void set_num_steps(uint8_t num_steps)
+  {
+    num_steps_ = num_steps;
+  }
+
+  void Configure(uint16_t* parameter, ControlMode control_mode)
+  {
+    set_step(0, parameter[0] >> 1);
+    set_step(1, parameter[1] >> 1);
+    set_step(2, parameter[2] >> 1);
+    set_step(3, parameter[3] >> 1);
+    set_num_steps(4);
+  }
+
+  void Process(const GateFlags* gate_flags, int16_t* out, size_t size)
+  {
+    while (size--) {
+      GateFlags gate_flag = *gate_flags++;
+      if (gate_flag & GATE_FLAG_RISING) {
+        ++step_;
+        if (reset_at_next_clock_) {
+          reset_at_next_clock_ = false;
+          step_ = 0;
+        }
+      }
+      if (num_steps_ > 2 && gate_flag & GATE_FLAG_AUXILIARY_RISING) {
+        reset_at_next_clock_ = true;
+      }
+      if (step_ >= num_steps_) {
+        step_ = 0;
+      }
+      *out++ = static_cast<int32_t>(steps_[step_]) * 40960 >> 16;
+    }
+  }
+
+  private:
+  uint8_t num_steps_;
+  uint8_t step_;
+  int16_t steps_[kMaxNumSteps];
+
+  bool reset_at_next_clock_;
+
+  DISALLOW_COPY_AND_ASSIGN(MiniSequencer);
+};
+
+} // namespace peaks
+
+#endif // PEAKS_MODULATIONS_MINI_SEQUENCER_H_

pure_adsr/pure_adsr.cc

@@ -11,6 +11,7 @@
 #include "pure_adsr/drivers/switches.h"
 #include "pure_adsr/gate_processor.h"
 #include "pure_adsr/io_buffer.h"
+#include "pure_adsr/mini_sequencer.h"
 #include "pure_adsr/multistage_envelope.h"
 
 using namespace avrlib;
@@ -36,6 +37,7 @@ Switch<DigitalInput<Gpio<PortD, 3>>> button_input;
 typedef AdcInputScanner AnalogInputs;
 
 MultistageEnvelope envelope;
+MiniSequencer sequencer;
 
 IOBuffer io_buffer;
 int16_t output_buffer[kBlockSize];
@@ -52,6 +54,7 @@ void Process(IOBuffer::Block* block, size_t size)
     if (read_value != pot_values[i]) { // TODO: apply filtering
       pot_values[i] = read_value;
       envelope.Configure(pot_values, CONTROL_MODE_FULL);
+      sequencer.Configure(pot_values, CONTROL_MODE_FULL);
     }
   }
 
@@ -61,6 +64,8 @@ void Process(IOBuffer::Block* block, size_t size)
     case MODE_ADSR:
       envelope.Process(block->input[i], output_buffer, size);
       break;
+    case MODE_SEQ:
+      sequencer.Process(block->input[i], output_buffer, size);
     default:
       break;
     }
@@ -89,11 +94,14 @@ void Init()
 
   io_buffer.Init();
   envelope.Init();
+  sequencer.Init();
 
   uint16_t pots[4];
   for (size_t i = 0; i < 4; i++)
     pots[4 - (i + 1)] = AnalogInputs::Read8(i) << 8;
   envelope.Configure(pots, CONTROL_MODE_FULL);
+  sequencer.Configure(pots, CONTROL_MODE_FULL);
+
   Timer<2>::Start();
 }
 
@@ -120,7 +128,7 @@ TIMER_0_TICK
     mode = MODE_SEQ;
     break;
   case 1:
-    mode = MODE_THREE;
+    mode = MODE_LFO;
     break;
   case 2:
     mode = MODE_ADSR;
@@ -135,7 +143,10 @@ TIMER_2_TICK
   --clock_divider_midi;
   if (!clock_divider_midi) {
     uint32_t gate_inputs = gate_input.Read();
-    gate_inputs |= button_input.pressed();
+
+    if (mode == MODE_ADSR || mode == MODE_SEQ)
+      gate_inputs |= button_input.pressed();
+
     IOBuffer::Slice slice = io_buffer.NextSlice(1);
     for (size_t i = 0; i < kNumChannels; ++i) {
       gate_flags = ExtractGateFlags(