Removing, for now, BREAK-less packet support. It doesn't feel like it…

… should go in this release but it might end up in a future one.

README.md

@@ -31,9 +31,6 @@ Some notable features of this library:
    API. Alternate start codes can not only be handled, for example, for Text
    Packets or System Information Packets (SIP), but responses can be sent back
    to the transmitter, for example for RDM.
-9. The receiver can, if configured to do so, handle BREAK-less packets. That is,
-   packets that don't start with a BREAK character. This is useful for receiving
-   RDM discovery response packets.
 
 ### Limitations
 
@@ -289,13 +286,6 @@ processing results when ready.
 
 A more complete example is beyond the scope of this README.
 
-### Receiving BREAK-less packets
-
-Protocols such as RDM require listening for packets that don't start with a
-BREAK character. The receiver can be configured to receive these packets by
-calling `Receiver::setAllowBreaklessPackets`. See also
-`Receiver::allowBreaklessPackets` to determine whether this mode is enabled.
-
 ## DMX transmit
 
 ### Code example

src/Receiver.cpp

@@ -68,8 +68,6 @@ Receiver::Receiver(HardwareSerial &uart)
     : TeensyDMX(uart),
       began_(false),
       state_{RecvStates::kIdle},
-      allowBreaklessPackets_(false),
-      breaklessStartTime_(0),
       buf1_{0},
       buf2_{0},
       activeBuf_(buf1_),
@@ -479,18 +477,6 @@ void Receiver::completePacket() {
 }
 
 void Receiver::checkPacketTimeout() {
-  // Breakless packets
-  if (state_ == RecvStates::kBreaklessData) {
-    uint32_t t = micros();
-    if ((t - breaklessStartTime_) > kMaxBreaklessPacketTime ||
-        (t - lastSlotEndTime_) > kMaxBreaklessIdleTime) {
-      // Don't count as a timeout because that's how we detect end-of-packet
-      // for breakless packets
-      completePacket();
-    }
-    return;
-  }
-
   if (state_ != RecvStates::kData) {
     return;
   }
@@ -588,35 +574,6 @@ void Receiver::receiveByte(uint8_t b) {
       break;
 
     case RecvStates::kIdle:
-      if (allowBreaklessPackets_) {
-        // First byte: Set packet start time
-        breaklessStartTime_ = eopTime - 44;
-        activeBufIndex_ = 0;
-        lastSlotEndTime_ = eopTime;
-        activeBuf_[activeBufIndex_++] = b;
-        if (activeBufIndex_ == kMaxDMXPacketSize) {
-          completePacket();
-          state_ = RecvStates::kSkipBreaklessData;
-        } else {
-          state_ = RecvStates::kBreaklessData;
-        }
-      }
-      return;
-
-    case RecvStates::kBreaklessData:
-      lastSlotEndTime_ = eopTime;
-      if ((eopTime - breaklessStartTime_) > kMaxBreaklessPacketTime) {
-        // Don't count as a timeout because that's how we detect end-of-packet
-        // for breakless packets
-        completePacket();
-        state_ = RecvStates::kSkipBreaklessData;
-      } else {
-        activeBuf_[activeBufIndex_++] = b;
-        if (activeBufIndex_ == kMaxDMXPacketSize) {
-          completePacket();
-          state_ = RecvStates::kSkipBreaklessData;
-        }
-      }
       return;
 
     default:

src/TeensyDMX.h

@@ -137,18 +137,6 @@ class Receiver final : public TeensyDMX {
 
   void end() override;
 
-  // Sets the receiver to allow BREAK-less packets. This supports RDM's
-  // discovery responses. By default, the maximum packet time is the same as for
-  // DMX and the maximum inter-slot idle time is 2.0ms.
-  void setAllowBreaklessPackets(bool flag) {
-    allowBreaklessPackets_ = flag;
-  }
-
-  // Returns whether the receiver allows BREAK-less packets.
-  bool allowBreaklessPackets() const {
-    return allowBreaklessPackets_;
-  }
-
   // Reads all or part of the latest packet into buf. This returns zero if len
   // is negative or zero, or if startChannel is negative or beyond
   // kMaxDMXPacketSize. This only reads up to the end of the packet if
@@ -268,8 +256,6 @@ class Receiver final : public TeensyDMX {
     kMAB,    // Mark after break
     kData,   // Packet data
     kIdle,   // The end of data for one packet has been reached
-    kBreaklessData,      // Breakless packet data
-    kSkipBreaklessData,  // Skip data beyond the packet length
   };
 
   // The maximum allowed packet time for receivers, either BREAK plus data,
@@ -284,10 +270,6 @@ class Receiver final : public TeensyDMX {
   // in microseconds, exclusive.
   static constexpr uint32_t kMaxDMXIdleTime = 1000000;
 
-  // Breakless packet timeout parameters, RDM Controller timings
-  static constexpr uint32_t kMaxBreaklessPacketTime = kMaxDMXPacketTime;
-  static constexpr uint32_t kMaxBreaklessIdleTime = 2100;
-
   // Disables all the UART IRQs so that variables can be accessed concurrently.
   // The IRQs are not disabled if began_ is false.
   void disableIRQs() const;
@@ -337,12 +319,6 @@ class Receiver final : public TeensyDMX {
   // Keeps track of what we're receiving.
   volatile RecvStates state_;
 
-  // Whether we allow BREAK-less packet.
-  volatile bool allowBreaklessPackets_;
-
-  // A BREAK-less packet's start time.
-  uint32_t breaklessStartTime_;
-
   // The framing-error start time, in microseconds. This needs to be accessed
   // from the same interrupt that triggered the framing error so that there's
   // a guarantee that it doesn't get changed.