fix(bkgpslog):Fix float calc in buffer PID adjust

[EVA-2020-02.git] / exec / bkgpslog

diff --git a/exec/bkgpslog b/exec/bkgpslog
index bf21dfcadd65eb0ffc452cc1fdd4e4635755e5b4..7a4487fd872bfcea28fbf833f56ae1181fff5b09 100755 (executable)
--- a/exec/bkgpslog
+++ b/exec/bkgpslog
@@ -29,10 +29,6 @@ declare -a argRecPubKeys # for processArguments function
 ## Initialize variables
 OPTION_VERBOSE=""; OPTION_ENCRYPT=""; OPTION_COMPRESS=""; OPTION_TMPDIR="";
 errReset=0; BUFFER_TTL_ADJ_FLOAT="";
-### PID Control factors
-K_P=1; # Gain for compensating buffer round lag
-T_I=1000; # Consider this number of past buffer rounds to eliminate error
-T_D=1; # Predict value this number of buffer rounds into the future
 
 #===BEGIN Declare local script functions===
 checkapp() {
@@ -951,6 +947,11 @@ magicBufferSleepPID() {
     # errorHistorySize=100;
     ## Define BUFFER_TTL in nanoseconds
     BUFFER_TTL_NS=$((BUFFER_TTL * 10**9)) && vbm "BUFFER_TTL_NS:$BUFFER_TTL_NS";
+
+    ### PID Control factors
+    K_P=1; # Gain for compensating buffer round lag
+    T_I="$((4*BUFFER_TTL_NS))"; # Consider this number of past nanoseconds to eliminate error
+    T_D="$((1*BUFFER_TTL_NS))"; # Predict value this number of nanoseconds into the future
     
     # Calculate Error, errNS, in nanoseconds
     ## Get current time
@@ -975,11 +976,11 @@ magicBufferSleepPID() {
     # for value in "${errorHistory[@]}"; do
     #  errReset=$(( errReset + ( value*BUFFER_TTL_NS ) ));
     # done;
-    errReset="$(( (errReset + (errNS*BUFFER_TTL_NS)) ))" && vbm "errResetTerm:$errResetTerm";
+    errReset="$(( (errReset + (errNS*BUFFER_TTL_NS)) ))" && vbm "errReset:$errReset";
 #    errResetx10e3="$(( ( errResetx10e3 + ( errNSx10e3 * BUFFER_TTL_NS ) )*10**3 ))" && vbm "errResetx10e3:$errResetx10e3";
 
     # Calculate errRate in nanoseconds per nanosecond
-    errRate="$(( errNS / BUFFER_TTL_NS ))" && vbm "errRateTerm:$errRateTerm";
+    errRate="$(( errNS / BUFFER_TTL_NS ))" && vbm "errRate:$errRate";
 #    errRatex10e3="$(( ( errNSx10e3 ) / BUFFER_TTL_NS ))" && vbm "errRatex10e3:$errRatex10e3";
     
     # Calculate PID control signal
@@ -998,7 +999,10 @@ magicBufferSleepPID() {
        yell "WARNING:Buffer lag adjustment yielded negative seconds.";
     fi;
     ## Calculate nanosecond remainder
-    BUFFER_TTL_ADJ_FLOATFRAC="$((BUFFER_TTL_NS - (BUFFER_TTL_ADJ_INT*(10**9)) ))" && vbm "BUFFER_TTL_ADJ_FLOATFRAC:$BUFFER_TTL_ADJ_FLOATFRAC";
+    ### Remove integer
+    BUFFER_TTL_ADJ_FLOATFRAC="$((BUFFER_TTL_ADJ_NS - (BUFFER_TTL_ADJ_INT*(10**9)) ))";
+    ### Calc absolute value of fraction (by removing '-' if present; see https://stackoverflow.com/a/47240327
+    BUFFER_TTL_ADJ_FLOATFRAC="${BUFFER_TTL_ADJ_FLOAT_FRAC#-}" && vbm "BUFFER_TTL_ADJ_FLOATFRAC:$BUFFER_TTL_ADJ_FLOATFRAC";
     ## Form float BUFFER_TTL_ADJ_FLOAT
     BUFFER_TTL_ADJ_FLOAT="$BUFFER_TTL_ADJ_INT"."$BUFFER_TTL_ADJ_FLOATFRAC" && vbm "BUFFER_TTL_ADJ_FLOAT:$BUFFER_TTL_ADJ_FLOAT";
     vbm "STATUS:Calculated adjusted BUFFER_TTL (seconds):$BUFFER_TTL_ADJ_FLOAT";