From 80a17415752e8becc43b4c9d3cd144c467c21cb4 Mon Sep 17 00:00:00 2001
From: Stephen Olesen <slepp@slepp.ca>
Date: Thu, 2 Jul 2015 01:24:55 -0600
Subject: [PATCH] Preliminary addition of static memory allocations for packet
 buffers. Fixed(?) DDS frequency calculation on-chip.

---
 AFSK.cpp | 25 +++++++++++++++++++++----
 AFSK.h   |  8 +++++++-
 DDS.cpp  |  2 +-
 3 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/AFSK.cpp b/AFSK.cpp
index 2e93d60..f89501b 100644
--- a/AFSK.cpp
+++ b/AFSK.cpp
@@ -24,6 +24,10 @@ volatile unsigned long lastRx = 0;
 
 #define T_BIT ((unsigned int)(9600/1200))
 
+#ifdef PACKET_PREALLOCATE
+SimpleFIFO<AFSK::Packet *,PPOOL_SIZE> preallocPool;
+#endif
+
 void AFSK::Encoder::process() {
   // Check what clock pulse we're on
   if(bitClock == 0) { // We are onto our next bit timing  
@@ -396,11 +400,16 @@ AFSK::Packet *AFSK::PacketBuffer::getPacket() volatile {
 void AFSK::Packet::init(unsigned short dlen) {
   //data = (unsigned char *)buf;
   ready = 0;
-  freeData = 1; //freeData;
+#ifdef PACKET_PREALLOCATE
+  freeData = 0;
+  maxLen = 128; // Put it here instead
+#else
+  freeData = 1;
+  dataPtr = (uint8_t *)malloc(dlen+16);
+  maxLen = dlen; // Put it here instead
+#endif
   type = PACKET_STATIC;
   len = 0; // We had a length, but don't put it here.
-  maxLen = dlen; // Put it here instead
-  dataPtr = (uint8_t *)malloc(dlen+16);
   dataPos = dataPtr;
   readPos = dataPtr;
   fcs = 0xffff;
@@ -411,7 +420,11 @@ AFSK::Packet *AFSK::PacketBuffer::makePacket(unsigned short dlen) {
   AFSK::Packet *p;
   ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
     //Packet *p = findPooledPacket();
+#ifdef PACKET_PREALLOCATE
+    p = preallocPool.dequeue();
+#else
     p = new Packet(); //(Packet *)malloc(sizeof(Packet));
+#endif
     if(p) // If allocated
       p->init(dlen);
   }
@@ -421,8 +434,11 @@ AFSK::Packet *AFSK::PacketBuffer::makePacket(unsigned short dlen) {
 // Free a packet struct, mainly convenience
 void AFSK::PacketBuffer::freePacket(Packet *p) {
   if(!p)
-  return;
+    return;
   ATOMIC_BLOCK(ATOMIC_RESTORESTATE) {
+#ifdef PACKET_PREALLOCATE
+    preallocPool.enqueue(p);
+#else
     p->free();
     /*unsigned char i;
     for(i = 0; i < PPOOL_SIZE; ++i)
@@ -431,6 +447,7 @@ void AFSK::PacketBuffer::freePacket(Packet *p) {
     if(i < PPOOL_SIZE)
     pStatus &= ~(1<<i);*/
     delete p;
+#endif
   }  
 }
   
diff --git a/AFSK.h b/AFSK.h
index 13a33f0..694b50e 100644
--- a/AFSK.h
+++ b/AFSK.h
@@ -14,6 +14,7 @@
 
 #define PACKET_BUFFER_SIZE 2
 #define PACKET_STATIC 0
+//#define PACKET_PREALLOCATE
 
 // This is with all the digis, two addresses, framing and full payload
 // Two more bytes are added for HDLC_ESCAPEs
@@ -105,7 +106,12 @@ public:
       return (fcs == 0xF0B8);
     }
   private:
-    uint8_t *dataPtr, *dataPos, *readPos;
+#ifdef PACKET_PREALLOCATE
+    uint8_t dataPtr[128];
+#else
+    uint8_t *dataPtr;
+#endif
+    uint8_t *dataPos, *readPos;
     unsigned short fcs;
   };
   
diff --git a/DDS.cpp b/DDS.cpp
index 388f794..8d0c02b 100644
--- a/DDS.cpp
+++ b/DDS.cpp
@@ -73,7 +73,7 @@ void DDS::setFrequency(unsigned short freq) {
     }
   } else {
     // BUG: Step rate isn't properly calculated here, it gets the wrong frequency
-    stepRate = (freq/(refclk+DDS_REFCLK_OFFSET)) * pow(2,ACCUMULATOR_BITS);
+    stepRate = pow(2,ACCUMULATOR_BITS)*freq / (refclk+DDS_REFCLK_OFFSET);
   }
 }