diff --git a/IIDirectForm1Filter.cpp b/IIRDirectForm1Filter.cpp
similarity index 100%
rename from IIDirectForm1Filter.cpp
rename to IIRDirectForm1Filter.cpp
diff --git a/Makefile b/Makefile
index 716a8f6..2091355 100644
--- a/Makefile
+++ b/Makefile
@@ -9,7 +9,7 @@ LDFLAGS = -g
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
+		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
 		ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o \
 		NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o \
 		P25Trellis.o P25Utils.o POCSAGControl.o POCSAGNetwork.o QR1676.o RemoteControl.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o \
diff --git a/Makefile.Pi b/Makefile.Pi
index 06ef859..a7d416c 100644
--- a/Makefile.Pi
+++ b/Makefile.Pi
@@ -9,7 +9,7 @@ LDFLAGS = -g -L/usr/local/lib
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o I2CController.o IIDirectForm1Filter.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
+		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
 		ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o \
 		NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o \
 		P25Trellis.o P25Utils.o POCSAGControl.o POCSAGNetwork.o QR1676.o RemoteControl.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o \
diff --git a/Makefile.Pi.Adafruit b/Makefile.Pi.Adafruit
index 5009315..09125e3 100644
--- a/Makefile.Pi.Adafruit
+++ b/Makefile.Pi.Adafruit
@@ -10,7 +10,7 @@ LDFLAGS = -g -L/usr/local/lib
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
+		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
 		ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o \
 		NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o \
 		P25Trellis.o P25Utils.o POCSAGControl.o POCSAGNetwork.o QR1676.o RemoteControl.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o \
diff --git a/Makefile.Pi.OLED b/Makefile.Pi.OLED
index 63be413..2ea260c 100644
--- a/Makefile.Pi.OLED
+++ b/Makefile.Pi.OLED
@@ -9,7 +9,7 @@ LDFLAGS = -g -L/usr/local/lib
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o I2CController.o IIDirectForm1Filter.o OLED.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
+		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o I2CController.o IIRDirectForm1Filter.o OLED.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
 		ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o \
 		NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o \
 		P25Trellis.o P25Utils.o POCSAGControl.o POCSAGNetwork.o QR1676.o RemoteControl.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o \
diff --git a/Makefile.Pi.PCF8574 b/Makefile.Pi.PCF8574
index 4c89696..1513f45 100644
--- a/Makefile.Pi.PCF8574
+++ b/Makefile.Pi.PCF8574
@@ -10,7 +10,7 @@ LDFLAGS = -g -L/usr/local/lib
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o IIDirectForm1Filter.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
+		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o HD44780.o I2CController.o IIRDirectForm1Filter.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o \
 		ModemSerialPort.o Mutex.o NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o \
 		NXDNLayer3.o NXDNLICH.o NXDNLookup.o NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o \
 		P25Trellis.o P25Utils.o POCSAGControl.o POCSAGNetwork.o QR1676.o RemoteControl.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o \
diff --git a/Makefile.Solaris b/Makefile.Solaris
index ffe9564..ec34917 100644
--- a/Makefile.Solaris
+++ b/Makefile.Solaris
@@ -9,7 +9,7 @@ LDFLAGS = -g
 OBJECTS = \
 		AMBEFEC.o BCH.o BPTC19696.o CASTInfo.o Conf.o CRC.o Display.o DMRControl.o DMRCSBK.o DMRData.o DMRDataHeader.o DMREMB.o DMREmbeddedData.o DMRFullLC.o \
 		DMRLookup.o DMRLC.o DMRNetwork.o DMRShortLC.o DMRSlot.o DMRSlotType.o DMRAccessControl.o DMRTA.o DMRTrellis.o DStarControl.o DStarHeader.o DStarNetwork.o \
-		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o IIDirectForm1Filter.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o \
+		DStarSlowData.o FMControl.o FMNetwork.o Golay2087.o Golay24128.o Hamming.o IIRDirectForm1Filter.o LCDproc.o Log.o MMDVMHost.o MobileGPS.o Modem.o ModemSerialPort.o Mutex.o \
 		NetworkInfo.o Nextion.o NullDisplay.o NullModem.o NXDNAudio.o NXDNControl.o NXDNConvolution.o NXDNCRC.o NXDNFACCH1.o NXDNLayer3.o NXDNLICH.o NXDNLookup.o \
 		NXDNNetwork.o NXDNSACCH.o NXDNUDCH.o P25Audio.o P25Control.o P25Data.o P25LowSpeedData.o P25Network.o P25NID.o P25Trellis.o P25Utils.o POCSAGControl.o \
 		POCSAGNetwork.o QR1676.o RemoteControl.o RS129.o RS241213.o RSSIInterpolator.o SerialController.o SerialPort.o SHA256.o StopWatch.o Sync.o TFTSerial.o \