TODO.md

+Mods:
+- sampling freq is now for TX, RX is downsampled (1,2,4)
+- SAMPLES_PER_SYMBOL -> RX_SAMPLES_PER_SYMBOL
+- removed TX_FACTOR
+  - TX_FACTOR*SAMPLES_PER_SYMBOL -> TX_SAMPLES_PER_SYMBOL
+- remved MOD_INDEX
+
+
+Check:
+-[ ] check proper timing and working of adda_activateTransmission
+  -[ ] SPI has been changed to run only after TX has been powered on
+-[ ] sample_time_t has been renamed to rx_sample_cnt_t
+  -[ ] check all occurances of sample_time_t for proper use
+  -[ ] check all occurances of rx_sample_cnt_t for proper use
+-[X] disable SPI / sampling when switching RX <-> TX
+-[X] check calculations in receive.c (are they in ticks?)
+
+-[X] removed occurances of
+  -[X] SAMPLES_PER_SYMBOL
+  -[X] TX_FACTOR
+  -[X] MS_TO_SYMBOLS
+  -[X] TX_SAMPLING_CLK_DIV
+  -[X] SYNC_MOD_INDEX
+-[X] definition of
+  -[X] US_TO_TICKS
+  -[X] MS_TO_TICKS
+  should now be in **TX** samples
+-[X] check time calculation (TX vs. slower RX speed)
+-[X] TX_SAMPLING_CLK_DIV is now SAMPLING_CLK_DIV
+-[X] correct use of
+  -[X] SAMPLING_CLK_DIV    -> TX
+  -[X] RX_SAMPLING_CLK_DIV -> RX
+  -[X] which is used for clock only?
+-[X] these must be in ticks now (200kHz)
+  -[X] TXOFF_OUTPUT_SETTLE_TICKS
+  -[X] TXOFF_SWITCH_DELAY_TICKS
+-[X] adda_wait has been removed (replaced by adda_waitTimerTicks)
+  -[X] check, if all usages of adda_waitTimerTicks() use correct time units
+  -[X] TXRX_TURNAROUND_TICKS has correct unit?
+-[X] mcu_adda.c
+  -[X] check all occurances of sampleCnt
+-[X] check that adda_getTimerTicks() is used with proper type (return)
+  -[X] it looks as though this is not the case!
+-[X] rename adda_getSampleLag -> adda_getRxSampleLagTicks
+  -[X] and check that is used with time/ticks properly!
+-[X] check initialize_hardware.c and timings
+-[X] check SPI baudrate!
+-[X] check if ranging_getDelay() is in ticks
+  -[X] ranging_setDelay() correctly converting?
+-[X] sync.c
+  -[X] dist, tMax, tFirst are sample counts, no time! > check all occurances
+  -[X] endOfPreambleCnt is a sample count
+  -[X] syncTime is in ticks!
+  -[X] sync_calcEndOfPreamble() is in sample count (not ticks)
+  -[X] variable stime is a sample count
+-[X] rx_sample_longcnt_t is declared but never used ...
+  -[X] was sample_longtime_t ever used? it would be the proper replacement
+-[X] agc.c: AGC_EVENT_MAX_DELAY_TICKS is used as ticks unit?
+-[X] freq_setSignalWindowSize() takes ticks as parameter?
+  -[X] where is signal window size used? is it / does it have to be scaled with RX_DOWNSAMPLE?
+  -[X] where is freq_getRxThreshold() used? is it / does it have to be scaled with RX_DOWNSAMPLE?
+  -[X] dito freq_getRxThresholdSq ?
+  -[X] dito freq_getRxThresholdPerc ?
+-[X] ranging_setDelay() uses ticks
+-[X] SIGNAL_THRESHOLD_MAX defined correctly (based on RX_SAMPLES_PER_SYMBOL)?
+-[X] SIGNAL_WINDOW_SIZE_MAX defined correctly (based on RX_SAMPLES_PER_SYMBOL)?
+
+
+Todo
+- agc.c
+  - define LP_NUM_SAMPLES per speed
+  - then divide by RX_SAMPLING_DIV (2^x) !
+
+
+
+-[x] aci_config.c
+  - Ausgabe: SAMPLING_FREQ, RX_DOWNSAMPLE, inv freq band
+

src/TODO

+=== GENERAL ===
+
+- remove legacy board support!
+
+
+=== AGC ===
+
+- failed gain stage change cannot be identified in software due to DMA use
+
+
+=== TX/RX switch sequencing ===
+
+verify the following behavior
+
+TX -> RX
+- wait TXOFF_OUTPUT_SETTLE_NS = 500 us: wait for output to settle
+- disconnect TX, connect RX
+- wait TXOFF_SWITCH_DELAY_NS = 500 us:
+- enable rx
+    - wait RX_ENABLE_TICKS = 2 ms
+    - set gain (if AGC disabled)
+- disable tx
+    - disconnects TX (to ensure it's disconnected)
+- switch to timer ISR
+- send shutdown command to DAC (stupid, since DAC could be disabled!)
+- wait until total delay is TXRX_TURNAROUND
+- restore agc
+- switch to ADC ISR
+
+RX -> TX
+- switch to DAC ISR
+- disable RX
+- enable TX
+- wait until RXTX complete
+- connect TX, disconnect RX
+
+- TX timings should be part of TX-BOARD implementation/def., not generic (in freqsetup.h)!
+
+
+=== DOWNSAMPLING ===
+
+- code for using receiver downsampling has been added
+- it is currently locked
+- for unlocking requirements, see @freqsetup.h
+
+- make sure that time cannot warp in the switchToxxxISR() functions
+
+- check meta calculation in receive_finish() in @receive.c
+
+
+=== HARDWARE SUPPORT ===
+
+- check TXRX turnaround sequence:
+
+
+=== UART ===
+
+https://github.com/MaJerle/stm32-usart-uart-dma-rx-tx
+
+- enable DMA for UART
+- process data in ISRs or main?
+
+
+=== HAL ===
+
+The HAL implementation needs to be redone, as it's a bit over-engineered and the mcu indirection is confusing.
+
+
 === PKTPIN ===
 
 - if we change modes, the pin behavior may be corrupted until the next trigger!

src/aci/aci.h

 /**
- * Copyright 2016-2019
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner,
  * Jan Heitmann, and
@@ -43,6 +43,8 @@
 #include "types.h"
 #include "acitypes.h"
 
+#include "error.h"
+
 #include <stdbool.h>
 #include <stdint.h>
 
@@ -68,14 +70,11 @@ aci_check(const mm_packet_t * pkt);
 /**
  * send a reply back to the host
  */
-inline void
+static inline void
 __attribute__((__always_inline__))
 aci_sendReply(const mm_packet_t * const pkt)
 {
-  // TODO improve this, it sucks.
-  while (! host_sendPacket((uint8_t *)pkt, MM_HEADER_LEN + pkt->header.len)) {
-    /* busy wait */
-  }
+  WAIT_TIMED(! host_sendPacket((uint8_t *)pkt, MM_HEADER_LEN + pkt->header.len));
 }
 
 

src/aci/csrc/aci_config.c

 /**
- * Copyright 2016-2020
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -36,6 +36,7 @@
 #include "aci.h"
 #include "aci/types/config_rsp.h"
 #include "aci_config.h"
+#include "freqsetup.h"
 
 #include <string.h>
 
@@ -59,6 +60,15 @@ extern char * RXAMP_NAME;
  * private functions
  */
 
+
+
+/**************************************************************************
+ * public functions
+ */
+
+#define xstr(s) str(s)
+#define str(s) #s
+
 uint8_t
 aci_config_fillReply(uint8_t * payload)
 {
@@ -93,6 +103,12 @@ aci_config_fillReply(uint8_t * payload)
   strcat((char *)payload, "majority,");
 #endif
 
+  // sampling frequency
+  strcat((char *)payload, xstr(SAMPLING_FREQ));
+  strcat((char *)payload, ":");
+  strcat((char *)payload, xstr(RX_DOWNSAMPLE));
+  strcat((char *)payload, "Hz,");
+  
   // high speed option (shorter symbols)
 #ifdef HIGHSPEED
   strcat((char *)payload, "hi-sp,");
@@ -109,6 +125,9 @@ aci_config_fillReply(uint8_t * payload)
   
   // freq table origin
   strcat((char *)payload, LUT_SRC);
+#ifdef INVERT_FREQBAND
+  strcat((char *)payload, ",inv");
+#endif
   strcat((char *)payload, ",");
   
   // tx amp board
@@ -130,10 +149,6 @@ aci_config_fillReply(uint8_t * payload)
 
 
 
-/**************************************************************************
- * public functions
- */
-
 void
 aci_config_processCmd(__attribute__ ((unused)) const mm_packet_t * pkt)
 {

src/aci/csrc/aci_peakwinlen.c

 /**
- * Copyright 2016-2019
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -57,7 +57,7 @@ aci_peakwinlen_fillReply(uint8_t * payload)
   aci_peakwinlen_cmd_t  * p = (aci_peakwinlen_cmd_t *)payload;
 
   // TODO check length ...
-  p->winlen = HTONS( TICKS_TO_US( freq_getSignalWindowSize() ) );
+  p->winlen = HTONS( RXCNT_TO_US( freq_getSignalWindowSize() ) );
 
   return sizeof(aci_peakwinlen_cmd_t);
 }
@@ -73,7 +73,7 @@ aci_peakwinlen_processCmd(const mm_packet_t * pkt)
 {
   if (pkt->header.len == sizeof(aci_peakwinlen_cmd_t)) {
     aci_peakwinlen_cmd_t * p = (aci_peakwinlen_cmd_t *)(pkt->payload);
-    freq_setSignalWindowSize(US_TO_TICKS( NTOHS(p->winlen) ));
+    freq_setSignalWindowSize(US_TO_RXCNT( NTOHS(p->winlen) ));
   }
 }
 

src/aci/csrc/aci_pktpin.c

 /**
- * Copyright 2021
+ * Copyright 2021-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).

src/aci/csrc/aci_pktpin.h

 /**
- * Copyright 2021
+ * Copyright 2021-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).

src/aci/csrc/aci_powerlevel.c

 /**
- * Copyright 2016-2019
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -66,12 +66,12 @@ aci_powerlevel_fillReply(uint8_t * payload)
   // @see channelquality.h/c for details on the method
   Umean = 0;
   Ueff  = 0;
-  for (i = 0; i < SAMPLES_PER_SYMBOL; i++) {
+  for (i = 0; i < RX_SAMPLES_PER_SYMBOL; i++) {
     while (! adda_getSample(&sample)) { ; }
     Ueff += fp16_square(sample);
     Umean += sample;
   }
-  p->power = channelquality_calcPowerLevel(Ueff, Umean, SAMPLES_PER_SYMBOL, 1);  // the reference is a simple sine (useful?)
+  p->power = channelquality_calcPowerLevel(Ueff, Umean, RX_SAMPLES_PER_SYMBOL, 1);  // the reference is a simple sine (useful?)
 
   return sizeof(aci_powerlevel_rsp_t);
 }

src/aci/csrc/aci_rangingdelay.c

 /**
- * Copyright 2016-2019
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner,
  * Jan Heitmann, and
@@ -56,7 +56,7 @@ aci_rangingdelay_fillReply(uint8_t * payload)
   aci_rangingdelay_cmd_t * p = (aci_rangingdelay_cmd_t *)payload;
 
   // payload
-  p->rangingdelay = HTONL(TICKS_TO_MS(ranging_getDelay()));
+  p->rangingdelay = HTONL(TICKS_TO_MS(ranging_getDelayTicks()));
 
   return sizeof(aci_rangingdelay_cmd_t);
 }
@@ -71,7 +71,7 @@ void
 aci_rangingdelay_processCmd(const mm_packet_t * pkt)
 {
   if (pkt->header.len == sizeof(aci_rangingdelay_cmd_t)) {
-    ranging_setDelay(MS_TO_TICKS(NTOHL(((aci_rangingdelay_cmd_t *)pkt->payload)->rangingdelay)));
+    ranging_setDelayTicks(MS_TO_TICKS(NTOHL(((aci_rangingdelay_cmd_t *)pkt->payload)->rangingdelay)));
   }
 }
 

src/aci/csrc/aci_rxlevel.c

 /**
- * Copyright 2016-2019
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -75,7 +75,7 @@ aci_rxlevel_fillReply(uint8_t * payload)
   // calculate power
   // @see sync.c for details on method
   memset(integral, 0, sizeof(integral));
-  for (i = 0; i < SAMPLES_PER_SYMBOL; i++) {
+  for (i = 0; i < RX_SAMPLES_PER_SYMBOL; i++) {
     while (! adda_getSample(&sample)) { ; }
 
     for (symb = 0; symb < NUM_SYMBOLS; symb++) {

src/aci/csrc/aci_test_freq.c

 /**
- * Copyright 2016-2018
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -86,7 +86,7 @@ aci_test_freq_processCmd(const mm_packet_t * pkt)
   adda_activateTransmission();
 
   // send out selected frequency
-  for (i = 0; i < TX_FACTOR*SAMPLES_PER_SYMBOL; i++) {
+  for (i = 0; i < TX_SAMPLES_PER_SYMBOL; i++) {
     adda_setSample(fp16_mul(FREQ_TXLIST[idx][i], gain));
   }
 

src/aci/csrc/aci_test_noise.c

 /**
- * Copyright 2016-2018
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -60,7 +60,7 @@ aci_test_noise_processCmd(const mm_packet_t * pkt)
   uint16_t  i, j;
   uint16_t  idx;  // prevent any wrap arounds when using uint8
   fp32_t    scale;
-  fp16_t    testSig[TX_FACTOR*SAMPLES_PER_SYMBOL];
+  fp16_t    testSig[TX_SAMPLES_PER_SYMBOL];
   aci_test_noise_cmd_t * p = (aci_test_noise_cmd_t *)pkt->payload;
   
   // sanity check
@@ -87,7 +87,7 @@ aci_test_noise_processCmd(const mm_packet_t * pkt)
   }
   
   // prepare test signal
-  for (i = 0; i < TX_FACTOR*SAMPLES_PER_SYMBOL; i++) {
+  for (i = 0; i < TX_SAMPLES_PER_SYMBOL; i++) {
     fp32_t tmp;
     tmp = 0;
     for (idx = 0; idx < FREQ_LIST_NUM; idx += p->step) {
@@ -101,7 +101,7 @@ aci_test_noise_processCmd(const mm_packet_t * pkt)
 
   for (j = 0; j < p->dur; j++) {
     // send out next frequency
-    for (i = 0; i < TX_FACTOR*SAMPLES_PER_SYMBOL; i++) {
+    for (i = 0; i < TX_SAMPLES_PER_SYMBOL; i++) {
       adda_setSample(testSig[i]);
     }
   }

src/aci/csrc/aci_test_sound.c

@@ -53,7 +53,7 @@
  * This file was auto-generated by genFsk.py for the range 4500:1000:4500 Hz
 */
 
-static const fp16_t FREQ_TEST_SOUND[TX_FACTOR * SAMPLES_PER_SYMBOL] = {
+static const fp16_t FREQ_TEST_SOUND[TX_SAMPLES_PER_SYMBOL] = {
   0x0000, 0x0964, 0x1294, 0x1b5d, 0x238e, 0x2afa, 0x3179, 0x36e5,
   0x3b20, 0x3e14, 0x3fb1, 0x3fec, 0x3ec5, 0x3c42, 0x3871, 0x3367,
   0x2d41, 0x261f, 0x1e2b, 0x158f, 0x0c7c, 0x0323, 0xf9bb, 0xf074,
@@ -126,7 +126,7 @@ static const fp16_t FREQ_TEST_SOUND[TX_FACTOR * SAMPLES_PER_SYMBOL] = {
  */
 
 // determine number of symbols from duration in ms, round to nearest
-#define MS_TO_SYMBOLS(t)  ((MS_TO_TICKS(t) + SAMPLES_PER_SYMBOL / 2) / SAMPLES_PER_SYMBOL)
+#define MS_TO_TX_SYMBOLS(t)  ((MS_TO_TICKS(t) + TX_SAMPLES_PER_SYMBOL / 2) / TX_SAMPLES_PER_SYMBOL)
 
 
 /**************************************************************************
@@ -146,11 +146,11 @@ aci_test_sound_processCmd(const mm_packet_t * pkt)
   }
 
   // obtain and check parameters
-  dur = MS_TO_SYMBOLS(10 * p->dur);  // p->dur in 1/100 ms
-  if (dur < MS_TO_SYMBOLS(10)) {
-    dur = MS_TO_SYMBOLS(10);
-  } else if (dur > MS_TO_SYMBOLS(2500)) {
-    dur = MS_TO_SYMBOLS(2500);
+  dur = MS_TO_TX_SYMBOLS(10 * p->dur);  // p->dur in 1/100 ms
+  if (dur < MS_TO_TX_SYMBOLS(10)) {
+    dur = MS_TO_TX_SYMBOLS(10);
+  } else if (dur > MS_TO_TX_SYMBOLS(2500)) {
+    dur = MS_TO_TX_SYMBOLS(2500);
   }
 
   // init tx mode
@@ -158,7 +158,7 @@ aci_test_sound_processCmd(const mm_packet_t * pkt)
 
   // repeat symbol to match duration
   for (j = 0; j < dur; j++) {
-    for (i = 0; i < TX_FACTOR*SAMPLES_PER_SYMBOL; i++) {
+    for (i = 0; i < TX_SAMPLES_PER_SYMBOL; i++) {
       adda_setSample(FREQ_TEST_SOUND[i]);
     }
   }

src/aci/csrc/aci_test_sweep.c

 /**
- * Copyright 2016-2018
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -77,7 +77,7 @@ aci_test_sweep_processCmd(const mm_packet_t * pkt)
 
   for (idx = 0; idx < FREQ_LIST_NUM; idx++) {
     // send out next frequency
-    for (i = 0; i < TX_FACTOR*SAMPLES_PER_SYMBOL; i++) {
+    for (i = 0; i < TX_SAMPLES_PER_SYMBOL; i++) {
       fp16_t  s;
       s = FREQ_TXLIST[idx][i];
       if (p->gc) {
@@ -88,7 +88,7 @@ aci_test_sweep_processCmd(const mm_packet_t * pkt)
 
     // add silence (multiple symbols)
     // TODO sanity check (int overflow)
-    for (i = 0; i < p->gap * TX_FACTOR*SAMPLES_PER_SYMBOL; i++) {
+    for (i = 0; i < p->gap * TX_SAMPLES_PER_SYMBOL; i++) {
       adda_setNeutralSample();
     }
   }

src/agc.c

 /**
- * Copyright 2016-2019
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -54,25 +54,22 @@ static uint8_t   gainLvl = DEFAULT_GAIN_LEVEL;
 //#define AGC_WAIT_INC          ((uint16_t)(1 + (SAMPLES_PER_SYMBOL *  2)))  // decay time
 //#define AGC_WAIT_DEC          ((uint16_t)(1 + (SAMPLES_PER_SYMBOL / 10)))  // attack time
 // FIXME it's very dangerous to make this dependent on symbol length rather than time!
-#define AGC_WAIT_INC          ((uint16_t)(1 + (SAMPLES_PER_SYMBOL *  1)))  // decay time
-#define AGC_WAIT_DEC          ((uint16_t)(1 + (SAMPLES_PER_SYMBOL / 16)))  // attack time
+#define AGC_WAIT_INC          ((uint16_t)(1 + (RX_SAMPLES_PER_SYMBOL *  1)))  // decay time
+#define AGC_WAIT_DEC          ((uint16_t)(1 + (RX_SAMPLES_PER_SYMBOL / 16)))  // attack time
 static uint16_t waitInc = 0;
 static uint16_t waitDec = 0;
 
-// NOTE, ticks delivered (used) are raw (i.e., not scaled with to RX units (div. by TX factor))
-// so we simply multiply our time with that rather than using slow division in the code
-#define AGC_EVENT_MAX_DELAY   (TX_FACTOR * US_TO_TICKS(100))
+// NOTE time ticks are at SAMPLING_FREQ, not at (possible) RX down-sampled rate
+#define AGC_EVENT_MAX_DELAY_TICKS   US_TO_TICKS(100)
 static sample_time_t  agcEvTime;
 static void (* agcEvHandler)(void) = NULL;
 
 
-//#define FB_EWMA  64  // -> x_i = (FB_EWMA-1)/FB_EWMA* x_{i-1} + 1/FB_EWMA * x
-#if SAMPLING_FREQ == 50000
-#   define LP_NUM_SAMPLES  16  // MUST be a power of two!
-#elif SAMPLING_FREQ == 200000
+// TODO add other frequencies and down samplings
+#if SAMPLING_FREQ == FREQ_200kHz && RX_DOWNSAMPLE == RX_SAMPLING_DIV1
 #   define LP_NUM_SAMPLES  64  // MUST be a power of two!
 #else
-#   error "sampling frequency not supported by AGC"
+#   error "sampling frequency or RX downsampling not supported by AGC"
 #endif
 #define LP_NUM_MASK     (LP_NUM_SAMPLES-1)
 
@@ -109,7 +106,7 @@ static void (* agcEvHandler)(void) = NULL;
 #define CONTROL_THRESH_SIGNAL_LOW   ((fp32_t)(FP32_INV(GAIN_STEP_SQR) * CONTROL_TARGET_SIGNAL * LP_NUM_SAMPLES))
 
 // feedback value (sum inside window)
-static fp32_t  fb = 0; // use larger data type to avoid casts during calculation (EWMA)
+static fp32_t  fb = 0; // use larger data type to cope with larger sums of fp16_t
 
 // current thresholds
 static fp32_t  threshHigh;
@@ -309,7 +306,7 @@ agc_checkAction(sample_time_t ticks)
   }
   
   // call handler and reset
-  if (ticks - agcEvTime <= AGC_EVENT_MAX_DELAY) {
+  if (ticks - agcEvTime <= AGC_EVENT_MAX_DELAY_TICKS) {
     agcEvHandler();
   }
   agcEvHandler = NULL;

src/batvoltage.c

 /**
- * Copyright 2016-2019
+ * Copyright 2016-2024
  * 
  * Jan Heitmann,
  * Bernd-Christian Renner, and
@@ -49,16 +49,16 @@
 
 #define BATVOL_FACTOR (((BATVOL_RL+BATVOL_RH)*BATVOL_VREF) / BATVOL_RL)
 
-static uint16_t batteryVoltage = 0;
+static uint16_t batteryVoltage = 0;     // [mV]
 
-static uint8_t  batVolThreshState = 0;
+static uint8_t  batVolThreshState = 0;  // index of BATVOL_THRESH
 
 static bool     batVolInit = false;
 
 // values include 200mV diode drop
 // FIXME this is HW specific, so move where it belongs
 static const uint16_t
-batvolThresh[] = {
+BATVOL_THRESH[] = {
   11040,  // crit, ca 25% [mV] 
   11310,  // low,  ca 50% [mV]
   11750,  // good, ca 75% [mV] 
@@ -70,7 +70,7 @@ batvolThresh[] = {
 // };
 
     
-#define BATVOL_THRESH_NUM  (sizeof(batvolThresh)/sizeof(batvolThresh[0]))
+#define BATVOL_THRESH_NUM  (sizeof(BATVOL_THRESH)/sizeof(BATVOL_THRESH[0]))
 
 #define BATVOL_CYCLE_LEN   20  // must be larger than 2*(BATVOL_THRESH_NUM+1)
 
@@ -106,7 +106,7 @@ adc_handler(uint16_t raw) {
   // recharging battery or lab supply (whch might increase)
   uint8_t  i;
   for (i = 0; i < BATVOL_THRESH_NUM; i++) {
-    if (batteryVoltage < batvolThresh[i]) {
+    if (batteryVoltage < BATVOL_THRESH[i]) {
       break;
     }
   }
@@ -118,9 +118,9 @@ adc_handler(uint16_t raw) {
 
 // callback from MCU timer interface
 // blinking pattern
-// n blinks per cycle -> voltage below batvolThresh[n-1]
+// n blinks per cycle -> voltage below BATVOL_THRESH[n-1]
 // min is 1 blink (so that the user knows the device still works)
-// if voltage exceeds maximum (last entry in batvolThresh), permanent blinking
+// if voltage exceeds maximum (last entry in BATVOL_THRESH), permanent blinking
 void
 alivetimer_handler()
 {

src/channelquality.c

 /**
- * Copyright 2016-2019
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -100,7 +100,7 @@ channelquality_calcSignalLevel(fp64_t rxLevel, uint32_t numBits, uint8_t numFreq
   // relAmpl    = 2 / N * mean
   // relFreqs   = relAmpl / (1 / numFreqs) = relAmpl * numFreqs
   // TODO inefficient: possible to convert to (smaller) uints?
-  uint32_t  res = fp64_toUint( 100 * fp64_sqrt( rxLevel / numBits ) * numFreqs * 2 / SAMPLES_PER_SYMBOL );
+  uint32_t  res = fp64_toUint( 100 * fp64_sqrt( rxLevel / numBits ) * numFreqs * 2 / RX_SAMPLES_PER_SYMBOL );
   
   return res > RSSI_MAX ? RSSI_MAX : res;
   

src/config.mk.dist

@@ -44,12 +44,22 @@ aci/csrc
 # enable debug pins
 CFLAGS += -DPIN_DEBUG
 
+# setup sampling rate (SAMPLING_FREQ) and RX downsampling sending
+# (RX_DOWNSAMPLE), not all combinations are supported with every
+# communication band
+# CFLAGS += -DSAMPLING_FREQ=FREQ_200kHz
+# CFLAGS += -DRX_DOWNSAMPLE=RX_SAMPLING_DIV1
+
 # enable ACI sample command
 CFLAGS += -DACI_SAMPLE_ENABLE
 
 # enable TX gain compensation to equalize hydrophone levels
 CFLAGS += -DTXGAIN_COMP
 
+# set default transducer
+# see TRANSDUCER_* in freq_setup.h for available options
+# CFLAGS += -DTRANSDUCER_DFLT=TRANSDUCER_AS1_ORIG
+
 # set spreading/despreading method
 # - best bit: only use best bit (ignore all others)
 # - majority: make a majority vote (useful only for odd number)
@@ -68,6 +78,12 @@ CFLAGS += -DSYNC_AUTO_NOISE
 # use wide band
 # CFLAGS += -DWIDEBAND
 
+# invert frequency band
+# this option should be used in combination with
+# non-wideband, if the hydrophone is much louder
+# towards the higher end of the overall band
+# CFLAGS += -DINVERT_FREQBAND
+
 # frequency band definitions dir
 LUT_SRC = os/fsk_25-60
 

src/error.h

+/**
+ * Copyright 2023
+ * 
+ * Bernd-Christian Renner and
+ * Hamburg University of Technology (TUHH).
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+
+#include <hal_gpio.h>
+
+
+#define TIMEOUT_MS  100
+
+#define WAIT_TIMED(cond) \
+  do { \
+    uint32_t tickstart = HAL_GetTick(); \
+    while (cond) { \
+      if (TIMEOUT_MS == 0 || (HAL_GetTick() - tickstart) > TIMEOUT_MS) { \
+        led_on(LED_1); \
+        led_on(LED_2); \
+        led_on(LED_3); \
+        led_on(LED_4); \
+        led_on(LED_5); \
+        while (true) { /* dead */ } \
+      } \
+    } \
+  } while (false);

src/freqsetup.c

 /**
- * Copyright 2016-2019
+ * Copyright 2016-2023
  * 
  * Bernd-Christian Renner, and
  * Hamburg University of Technology (TUHH).
@@ -592,7 +592,7 @@ freq_getTxGainByIndex(uint8_t i)
 }
 
 
-uint16_t
+rx_sample_cnt_t
 freq_getSignalWindowSize()
 {
   return signalWindowSize;
@@ -600,7 +600,7 @@ freq_getSignalWindowSize()
 
 
 void
-freq_setSignalWindowSize(uint16_t newSize)
+freq_setSignalWindowSize(rx_sample_cnt_t newSize)
 {
   if (newSize <= SIGNAL_WINDOW_SIZE_MAX) {
     signalWindowSize = newSize;