diff --git a/csdr.c b/csdr.c
index 52de1ab..6a0c42a 100644
--- a/csdr.c
+++ b/csdr.c
@@ -163,6 +163,8 @@ int clone_(int bufsize_param)
 		}
 }
 
+#define FREAD_U8	fread (input_buffer,	sizeof(unsigned char), the_bufsize, stdin)
+#define FWRITE_U8 	fwrite (output_buffer,	sizeof(unsigned char), the_bufsize, stdout)
 #define FREAD_R		fread (input_buffer,	sizeof(float),		the_bufsize, stdin)
 #define FREAD_C		fread (input_buffer,	sizeof(float)*2,	the_bufsize, stdin)
 #define FWRITE_R 	fwrite (output_buffer,	sizeof(float),		the_bufsize, stdout)
@@ -352,7 +354,7 @@ int main(int argc, char *argv[])
 
 		char** fifo_buffers = (char**)malloc(sizeof(char*)*fifo_num_buffers);
 		for(int i=0;i<fifo_num_buffers;i++) fifo_buffers[i]=(char*)malloc(sizeof(char)*fifo_buffer_size);
-		
+
 		SET_NONBLOCK(STDIN_FILENO);
 		SET_NONBLOCK(STDOUT_FILENO);
 
@@ -375,7 +377,7 @@ int main(int argc, char *argv[])
 		for(;;)
 		{
 			select(highfd, &read_fds, NULL, NULL, NULL);
-			
+
 			//try to read until buffer is full
 			if(FD_ISSET(STDIN_FILENO, &read_fds)) for(;;)
 			{
@@ -383,9 +385,9 @@ int main(int argc, char *argv[])
 				//fprintf(stderr, "r %d %d | %d %d\n", read_bytes, fifo_buffer_size-fifo_actual_buffer_rd_pos, fifo_actual_buffer_rd, fifo_actual_buffer_rd_pos);
 				if(!read_bytes || ((read_bytes<0)&&(fifo_error=read_bytes)) ) break;
 				fifo_actual_buffer_rd_pos+=read_bytes;
-				if(!((fifo_actual_buffer_rd==fifo_actual_buffer_wr-1)||(fifo_actual_buffer_wr==0&&fifo_actual_buffer_rd==fifo_num_buffers-1))) 
+				if(!((fifo_actual_buffer_rd==fifo_actual_buffer_wr-1)||(fifo_actual_buffer_wr==0&&fifo_actual_buffer_rd==fifo_num_buffers-1)))
 				{
-					if(fifo_actual_buffer_rd_pos==fifo_buffer_size) 
+					if(fifo_actual_buffer_rd_pos==fifo_buffer_size)
 					{
 						fifo_overrun_shown = 0;
 						fifo_actual_buffer_rd++;
@@ -394,8 +396,8 @@ int main(int argc, char *argv[])
 					}
 				}
 				else
-				{	
-					if(fifo_actual_buffer_rd_pos==fifo_buffer_size) 
+				{
+					if(fifo_actual_buffer_rd_pos==fifo_buffer_size)
 					{
 						fifo_actual_buffer_rd_pos = 0; //rewrite same buffer
 						if(!fifo_overrun_shown) { fifo_overrun_shown=1; fprintf(stderr, "fifo: circular buffer full, dropping samples\n"); }
@@ -409,8 +411,8 @@ int main(int argc, char *argv[])
 				int written_bytes=write(STDOUT_FILENO, fifo_buffers[fifo_actual_buffer_wr]+fifo_actual_buffer_wr_pos, fifo_buffer_size-fifo_actual_buffer_wr_pos);
 				//fprintf(stderr, "w %d %d | %d %d\n", written_bytes, fifo_buffer_size-fifo_actual_buffer_wr_pos, fifo_actual_buffer_wr, fifo_actual_buffer_wr_pos);
 				if(!written_bytes || ((written_bytes<0)&&(fifo_error=written_bytes)) ) break;
-				fifo_actual_buffer_wr_pos+=written_bytes;		
-				if(fifo_actual_buffer_wr_pos==fifo_buffer_size) 
+				fifo_actual_buffer_wr_pos+=written_bytes;
+				if(fifo_actual_buffer_wr_pos==fifo_buffer_size)
 				{
 					fifo_actual_buffer_wr++;
 					fifo_actual_buffer_wr_pos = 0;
@@ -1832,6 +1834,34 @@ int main(int argc, char *argv[])
 		}
 	}
 
+	if(!strcmp(argv[1],"bpsk31_varicode2ascii_sy_u8")) //not tested
+	{
+		unsigned long long status_shr = 0;
+		unsigned char output;
+		if(!sendbufsize(initialize_buffers())) return -2;
+		unsigned char i=0;
+		for(;;)
+		{
+			if((output=psk31_varicode_push(&status_shr, getchar()))) { putchar(output); fflush(stdout); }
+			if(i++) continue; //do the following at every 256th execution of the loop body:
+			FEOF_CHECK;
+			TRY_YIELD;
+		}
+	}
+
+	if(!strcmp(argv[1],"invert_sy_sy")) //not tested
+	{
+		if(!sendbufsize(initialize_buffers())) return -2;
+		unsigned char i=0;
+		for(;;)
+		{
+			putchar(!getchar());
+			if(i++) continue; //do the following at every 256th execution of the loop body:
+			FEOF_CHECK;
+			TRY_YIELD;
+		}
+	}
+
 	if(!strcmp(argv[1],"none"))
 	{
 		return 0;
diff --git a/libcsdr.c b/libcsdr.c
index e3b01bf..5dd38c7 100644
--- a/libcsdr.c
+++ b/libcsdr.c
@@ -949,6 +949,252 @@ void logpower_cf(complexf* input, float* output, int size, float add_db)
 	for(int i=0;i<size;i++) output[i]=10*output[i]+add_db; //@logpower_cf: pass 3
 }
 
+/*
+  _____  _       _ _        _       _                          _
+ |  __ \(_)     (_) |      | |     | |                        | |
+ | |  | |_  __ _ _| |_ __ _| |   __| | ___ _ __ ___   ___   __| |
+ | |  | | |/ _` | | __/ _` | |  / _` |/ _ \ '_ ` _ \ / _ \ / _` |
+ | |__| | | (_| | | || (_| | | | (_| |  __/ | | | | | (_) | (_| |
+ |_____/|_|\__, |_|\__\__,_|_|  \__,_|\___|_| |_| |_|\___/ \__,_|
+            __/ |
+           |___/
+*/
+
+
+typedef struct psk31_varicode_item_s
+{
+	unsigned long long code;
+	int bitcount;
+	unsigned char ascii;
+} psk31_varicode_item_t;
+
+psk31_varicode_item_t psk31_varicode_items[] =
+{
+	{ .code = 0b1010101011,	.bitcount=10,	.ascii=0x00 }, //NUL, null
+	{ .code = 0b1011011011,	.bitcount=10,	.ascii=0x01 }, //SOH, start of heading
+	{ .code = 0b1011101101,	.bitcount=10,	.ascii=0x02 }, //STX, start of text
+	{ .code = 0b1101110111,	.bitcount=10,	.ascii=0x03 }, //ETX, end of text
+	{ .code = 0b1011101011,	.bitcount=10,	.ascii=0x04 }, //EOT, end of transmission
+	{ .code = 0b1101011111,	.bitcount=10,	.ascii=0x05 }, //ENQ, enquiry
+	{ .code = 0b1011101111,	.bitcount=10,	.ascii=0x06 }, //ACK, acknowledge
+	{ .code = 0b1011111101,	.bitcount=10,	.ascii=0x07 }, //BEL, bell
+	{ .code = 0b1011111111,	.bitcount=10,	.ascii=0x08 }, //BS, backspace
+	{ .code = 0b11101111,	.bitcount=8,	.ascii=0x09 }, //TAB, horizontal tab
+	{ .code = 0b11101,	.bitcount=5,	.ascii=0x0a }, //LF, NL line feed, new line
+	{ .code = 0b1101101111,	.bitcount=10,	.ascii=0x0b }, //VT, vertical tab
+	{ .code = 0b1011011101,	.bitcount=10,	.ascii=0x0c }, //FF, NP form feed, new page
+	{ .code = 0b11111,	.bitcount=5,	.ascii=0x0d }, //CR, carriage return (overwrite)
+	{ .code = 0b1101110101,	.bitcount=10,	.ascii=0x0e }, //SO, shift out
+	{ .code = 0b1110101011,	.bitcount=10,	.ascii=0x0f }, //SI, shift in
+	{ .code = 0b1011110111,	.bitcount=10,	.ascii=0x10 }, //DLE, data link escape
+	{ .code = 0b1011110101,	.bitcount=10,	.ascii=0x11 }, //DC1, device control 1
+	{ .code = 0b1110101101,	.bitcount=10,	.ascii=0x12 }, //DC2, device control 2
+	{ .code = 0b1110101111,	.bitcount=10,	.ascii=0x13 }, //DC3, device control 3
+	{ .code = 0b1101011011,	.bitcount=10,	.ascii=0x14 }, //DC4, device control 4
+	{ .code = 0b1101101011,	.bitcount=10,	.ascii=0x15 }, //NAK, negative acknowledge
+	{ .code = 0b1101101101,	.bitcount=10,	.ascii=0x16 }, //SYN, synchronous idle
+	{ .code = 0b1101010111,	.bitcount=10,	.ascii=0x17 }, //ETB, end of trans. block
+	{ .code = 0b1101111011,	.bitcount=10,	.ascii=0x18 }, //CAN, cancel
+	{ .code = 0b1101111101,	.bitcount=10,	.ascii=0x19 }, //EM, end of medium
+	{ .code = 0b1110110111,	.bitcount=10,	.ascii=0x1a }, //SUB, substitute
+	{ .code = 0b1101010101,	.bitcount=10,	.ascii=0x1b }, //ESC, escape
+	{ .code = 0b1101011101,	.bitcount=10,	.ascii=0x1c }, //FS, file separator
+	{ .code = 0b1110111011,	.bitcount=10,	.ascii=0x1d }, //GS, group separator
+	{ .code = 0b1011111011,	.bitcount=10,	.ascii=0x1e }, //RS, record separator
+	{ .code = 0b1101111111,	.bitcount=10,	.ascii=0x1f }, //US, unit separator
+	{ .code = 0b1,			.bitcount=1,	.ascii=0x20 }, //szóköz
+	{ .code = 0b111111111,	.bitcount=9,	.ascii=0x21 }, //!
+	{ .code = 0b101011111,	.bitcount=9,	.ascii=0x22 }, //"
+	{ .code = 0b111110101,	.bitcount=9,	.ascii=0x23 }, //#
+	{ .code = 0b111011011,	.bitcount=9,	.ascii=0x24 }, //$
+	{ .code = 0b1011010101,	.bitcount=10,	.ascii=0x25 }, //%
+	{ .code = 0b1010111011,	.bitcount=10,	.ascii=0x26 }, //&
+	{ .code = 0b101111111,	.bitcount=9,	.ascii=0x27 }, //'
+	{ .code = 0b11111011,	.bitcount=8,	.ascii=0x28 }, //(
+	{ .code = 0b11110111,	.bitcount=8,	.ascii=0x29 }, //)
+	{ .code = 0b101101111,	.bitcount=9,	.ascii=0x2a }, //*
+	{ .code = 0b111011111,	.bitcount=9,	.ascii=0x2b }, //+
+	{ .code = 0b1110101,	.bitcount=7,	.ascii=0x2c }, //,
+	{ .code = 0b110101,		.bitcount=6,	.ascii=0x2d }, //-
+	{ .code = 0b1010111,	.bitcount=7,	.ascii=0x2e }, //.
+	{ .code = 0b110101111,	.bitcount=9,	.ascii=0x2f }, ///
+	{ .code = 0b10110111,	.bitcount=8,	.ascii=0x30 }, //0
+	{ .code = 0b10111101,	.bitcount=8,	.ascii=0x31 }, //1
+	{ .code = 0b11101101,	.bitcount=8,	.ascii=0x32 }, //2
+	{ .code = 0b11111111,	.bitcount=8,	.ascii=0x33 }, //3
+	{ .code = 0b101110111,	.bitcount=9,	.ascii=0x34 }, //4
+	{ .code = 0b101011011,	.bitcount=9,	.ascii=0x35 }, //5
+	{ .code = 0b101101011,	.bitcount=9,	.ascii=0x36 }, //6
+	{ .code = 0b110101101,	.bitcount=9,	.ascii=0x37 }, //7
+	{ .code = 0b110101011,	.bitcount=9,	.ascii=0x38 }, //8
+	{ .code = 0b110110111,	.bitcount=9,	.ascii=0x39 }, //9
+	{ .code = 0b11110101,	.bitcount=8,	.ascii=0x3a }, //:
+	{ .code = 0b110111101,	.bitcount=9,	.ascii=0x3b }, //;
+	{ .code = 0b111101101,	.bitcount=9,	.ascii=0x3c }, //<
+	{ .code = 0b1010101,	.bitcount=7,	.ascii=0x3d }, //=
+	{ .code = 0b111010111,	.bitcount=9,	.ascii=0x3e }, //>
+	{ .code = 0b1010101111,	.bitcount=10,	.ascii=0x3f }, //?
+	{ .code = 0b1010111101,	.bitcount=10,	.ascii=0x40 }, //@
+	{ .code = 0b1111101,	.bitcount=7,	.ascii=0x41 }, //A
+	{ .code = 0b11101011,	.bitcount=8,	.ascii=0x42 }, //B
+	{ .code = 0b10101101,	.bitcount=8,	.ascii=0x43 }, //C
+	{ .code = 0b10110101,	.bitcount=8,	.ascii=0x44 }, //D
+	{ .code = 0b1110111,	.bitcount=7,	.ascii=0x45 }, //E
+	{ .code = 0b11011011,	.bitcount=8,	.ascii=0x46 }, //F
+	{ .code = 0b11111101,	.bitcount=8,	.ascii=0x47 }, //G
+	{ .code = 0b101010101,	.bitcount=9,	.ascii=0x48 }, //H
+	{ .code = 0b1111111,	.bitcount=7,	.ascii=0x49 }, //I
+	{ .code = 0b111111101,	.bitcount=9,	.ascii=0x4a }, //J
+	{ .code = 0b101111101,	.bitcount=9,	.ascii=0x4b }, //K
+	{ .code = 0b11010111,	.bitcount=8,	.ascii=0x4c }, //L
+	{ .code = 0b10111011,	.bitcount=8,	.ascii=0x4d }, //M
+	{ .code = 0b11011101,	.bitcount=8,	.ascii=0x4e }, //N
+	{ .code = 0b10101011,	.bitcount=8,	.ascii=0x4f }, //O
+	{ .code = 0b11010101,	.bitcount=8,	.ascii=0x50 }, //P
+	{ .code = 0b111011101,	.bitcount=9,	.ascii=0x51 }, //Q
+	{ .code = 0b10101111,	.bitcount=8,	.ascii=0x52 }, //R
+	{ .code = 0b1101111,	.bitcount=7,	.ascii=0x53 }, //S
+	{ .code = 0b1101101,	.bitcount=7,	.ascii=0x54 }, //T
+	{ .code = 0b101010111,	.bitcount=9,	.ascii=0x55 }, //U
+	{ .code = 0b110110101,	.bitcount=9,	.ascii=0x56 }, //V
+	{ .code = 0b101011101,	.bitcount=9,	.ascii=0x57 }, //W
+	{ .code = 0b101110101,	.bitcount=9,	.ascii=0x58 }, //X
+	{ .code = 0b101111011,	.bitcount=9,	.ascii=0x59 }, //Y
+	{ .code = 0b1010101101,	.bitcount=10,	.ascii=0x5a }, //Z
+	{ .code = 0b111110111,	.bitcount=9,	.ascii=0x5b }, //[
+	{ .code = 0b111101111,	.bitcount=9,	.ascii=0x5c }, //\
+	{ .code = 0b111111011,	.bitcount=9,	.ascii=0x5d }, //]
+	{ .code = 0b1010111111,	.bitcount=10,	.ascii=0x5e }, //^
+	{ .code = 0b101101101,	.bitcount=9,	.ascii=0x5f }, //_
+	{ .code = 0b1011011111,	.bitcount=10,	.ascii=0x60 }, //`
+	{ .code = 0b1011,		.bitcount=4,	.ascii=0x61 }, //a
+	{ .code = 0b1011111,	.bitcount=7,	.ascii=0x62 }, //b
+	{ .code = 0b101111,		.bitcount=6,	.ascii=0x63 }, //c
+	{ .code = 0b101101,		.bitcount=6,	.ascii=0x64 }, //d
+	{ .code = 0b11,			.bitcount=2,	.ascii=0x65 }, //e
+	{ .code = 0b111101,		.bitcount=6,	.ascii=0x66 }, //f
+	{ .code = 0b1011011,	.bitcount=7,	.ascii=0x67 }, //g
+	{ .code = 0b101011,		.bitcount=6,	.ascii=0x68 }, //h
+	{ .code = 0b1101,		.bitcount=4,	.ascii=0x69 }, //i
+	{ .code = 0b111101011,	.bitcount=9,	.ascii=0x6a }, //j
+	{ .code = 0b10111111,	.bitcount=8,	.ascii=0x6b }, //k
+	{ .code = 0b11011,		.bitcount=5,	.ascii=0x6c }, //l
+	{ .code = 0b111011,		.bitcount=6,	.ascii=0x6d }, //m
+	{ .code = 0b1111,		.bitcount=4,	.ascii=0x6e }, //n
+	{ .code = 0b111,		.bitcount=3,	.ascii=0x6f }, //o
+	{ .code = 0b111111,		.bitcount=6,	.ascii=0x70 }, //p
+	{ .code = 0b110111111,	.bitcount=9,	.ascii=0x71 }, //q
+	{ .code = 0b10101,		.bitcount=5,	.ascii=0x72 }, //r
+	{ .code = 0b10111,		.bitcount=5,	.ascii=0x73 }, //s
+	{ .code = 0b101,		.bitcount=3,	.ascii=0x74 }, //t
+	{ .code = 0b110111,		.bitcount=6,	.ascii=0x75 }, //u
+	{ .code = 0b1111011,	.bitcount=7,	.ascii=0x76 }, //v
+	{ .code = 0b1101011,	.bitcount=7,	.ascii=0x77 }, //w
+	{ .code = 0b11011111,	.bitcount=8,	.ascii=0x78 }, //x
+	{ .code = 0b1011101,	.bitcount=7,	.ascii=0x79 }, //y
+	{ .code = 0b111010101,	.bitcount=9,	.ascii=0x7a }, //z
+	{ .code = 0b1010110111,	.bitcount=10,	.ascii=0x7b }, //{
+	{ .code = 0b110111011,	.bitcount=9,	.ascii=0x7c }, //|
+	{ .code = 0b1010110101,	.bitcount=10,	.ascii=0x7d }, //}
+	{ .code = 0b1011010111,	.bitcount=10,	.ascii=0x7e }, //~
+	{ .code = 0b1110110101,	.bitcount=10,	.ascii=0x7f }, //DEL
+};
+
+const int n_psk31_varicode_items = sizeof(psk31_varicode_items) / sizeof(psk31_varicode_item_t);
+
+unsigned long long psk31_varicode_masklen_helper[] =
+{
+	0b0000000000000000000000000000000000000000000000000000000000000000,
+	0b0000000000000000000000000000000000000000000000000000000000000001,
+	0b0000000000000000000000000000000000000000000000000000000000000011,
+	0b0000000000000000000000000000000000000000000000000000000000000111,
+	0b0000000000000000000000000000000000000000000000000000000000001111,
+	0b0000000000000000000000000000000000000000000000000000000000011111,
+	0b0000000000000000000000000000000000000000000000000000000000111111,
+	0b0000000000000000000000000000000000000000000000000000000001111111,
+	0b0000000000000000000000000000000000000000000000000000000011111111,
+	0b0000000000000000000000000000000000000000000000000000000111111111,
+	0b0000000000000000000000000000000000000000000000000000001111111111,
+	0b0000000000000000000000000000000000000000000000000000011111111111,
+	0b0000000000000000000000000000000000000000000000000000111111111111,
+	0b0000000000000000000000000000000000000000000000000001111111111111,
+	0b0000000000000000000000000000000000000000000000000011111111111111,
+	0b0000000000000000000000000000000000000000000000000111111111111111,
+	0b0000000000000000000000000000000000000000000000001111111111111111,
+	0b0000000000000000000000000000000000000000000000011111111111111111,
+	0b0000000000000000000000000000000000000000000000111111111111111111,
+	0b0000000000000000000000000000000000000000000001111111111111111111,
+	0b0000000000000000000000000000000000000000000011111111111111111111,
+	0b0000000000000000000000000000000000000000000111111111111111111111,
+	0b0000000000000000000000000000000000000000001111111111111111111111,
+	0b0000000000000000000000000000000000000000011111111111111111111111,
+	0b0000000000000000000000000000000000000000111111111111111111111111,
+	0b0000000000000000000000000000000000000001111111111111111111111111,
+	0b0000000000000000000000000000000000000011111111111111111111111111,
+	0b0000000000000000000000000000000000000111111111111111111111111111,
+	0b0000000000000000000000000000000000001111111111111111111111111111,
+	0b0000000000000000000000000000000000011111111111111111111111111111,
+	0b0000000000000000000000000000000000111111111111111111111111111111,
+	0b0000000000000000000000000000000001111111111111111111111111111111,
+	0b0000000000000000000000000000000011111111111111111111111111111111,
+	0b0000000000000000000000000000000111111111111111111111111111111111,
+	0b0000000000000000000000000000001111111111111111111111111111111111,
+	0b0000000000000000000000000000011111111111111111111111111111111111,
+	0b0000000000000000000000000000111111111111111111111111111111111111,
+	0b0000000000000000000000000001111111111111111111111111111111111111,
+	0b0000000000000000000000000011111111111111111111111111111111111111,
+	0b0000000000000000000000000111111111111111111111111111111111111111,
+	0b0000000000000000000000001111111111111111111111111111111111111111,
+	0b0000000000000000000000011111111111111111111111111111111111111111,
+	0b0000000000000000000000111111111111111111111111111111111111111111,
+	0b0000000000000000000001111111111111111111111111111111111111111111,
+	0b0000000000000000000011111111111111111111111111111111111111111111,
+	0b0000000000000000000111111111111111111111111111111111111111111111,
+	0b0000000000000000001111111111111111111111111111111111111111111111,
+	0b0000000000000000011111111111111111111111111111111111111111111111,
+	0b0000000000000000111111111111111111111111111111111111111111111111,
+	0b0000000000000001111111111111111111111111111111111111111111111111,
+	0b0000000000000011111111111111111111111111111111111111111111111111,
+	0b0000000000000111111111111111111111111111111111111111111111111111,
+	0b0000000000001111111111111111111111111111111111111111111111111111,
+	0b0000000000011111111111111111111111111111111111111111111111111111,
+	0b0000000000111111111111111111111111111111111111111111111111111111,
+	0b0000000001111111111111111111111111111111111111111111111111111111,
+	0b0000000011111111111111111111111111111111111111111111111111111111,
+	0b0000000111111111111111111111111111111111111111111111111111111111,
+	0b0000001111111111111111111111111111111111111111111111111111111111,
+	0b0000011111111111111111111111111111111111111111111111111111111111,
+	0b0000111111111111111111111111111111111111111111111111111111111111,
+	0b0001111111111111111111111111111111111111111111111111111111111111,
+	0b0011111111111111111111111111111111111111111111111111111111111111,
+	0b0111111111111111111111111111111111111111111111111111111111111111
+};
+
+char psk31_varicode_push(unsigned long long* status_shr, unsigned char symbol)
+{
+	*status_shr=((*status_shr)<<1)|(!!symbol); //shift new bit in shift register
+	//fprintf(stderr,"*status_shr = %llx\n", *status_shr);
+	if((*status_shr)&0xFFF==0) return 0;
+	for(int i=0;i<n_psk31_varicode_items;i++)
+	{
+		//fprintf(stderr,"| i = %d | %llx ?= %llx | bitsall = %d\n", i, psk31_varicode_items[i].code<<2, (*status_shr)&psk31_varicode_masklen_helper[(psk31_varicode_items[i].bitcount+4)&63], (psk31_varicode_items[i].bitcount+4)&63);
+		if((psk31_varicode_items[i].code<<2)==((*status_shr)&psk31_varicode_masklen_helper[(psk31_varicode_items[i].bitcount+4)&63]))
+			{ /*fprintf(stderr,">>>>>>>>> %d %x %c\n", i,  psk31_varicode_items[i].ascii,  psk31_varicode_items[i].ascii);*/ return psk31_varicode_items[i].ascii; }
+
+	}
+	return 0;
+}
+
+
+
+/*
+
+*/
+
+
+
+
+
 /*
   _____        _                                            _
  |  __ \      | |                                          (_)
diff --git a/libcsdr.h b/libcsdr.h
index 8bcbc2a..419c064 100644
--- a/libcsdr.h
+++ b/libcsdr.h
@@ -178,3 +178,5 @@ void convert_f_i16(float* input, short* output, int input_size);
 void convert_i16_f(short* input, float* output, int input_size);
 
 int is_nan(float f);
+
+char psk31_varicode_push(unsigned long long* status_shr, unsigned char symbol);