Eurosignal: Allow dialing (paging) of Spare Digits

docs/eurosignal.html

@@ -212,6 +212,19 @@ Then the software will decode the received IDs and display them.
 You may also use both -R -T to allow the software to decode while it is encoding.
 </p>
 
+<p>
+You may append a station ID as command line option, so it is pre-selected and must not be typed in.
+You can also use digits like 'A', 'B', 'C', 'D' and 'E' to define Spare digits 1..5.
+I guess that these extension digis were never used, but it is supported by most pagers.
+Using a "Spare 2" as third digit looks like this:
+</p>
+
+<pre>
+
+# src/eurosignal/eurosignal -k B 12B456
+
+</pre>
+
 <hr><center>[<a href="index.html">Back to main page</a>]</center><hr>
 </td></tr></table></center>
 </body>

src/eurosignal/dsp.c

@@ -66,11 +66,11 @@ static struct dsp_digits {
 	{ '7',	"Digit 7",	 554.0,	0 },
 	{ '8',	"Digit 8",	 510.7,	0 },
 	{ '9',	"Digit 9",	 470.8,	0 },
-	{ 'A',	"Digit 10",	 433.9,	0 },
-	{ 'B',	"Digit 11",	 400.0,	0 },
-	{ 'C',	"Digit 12",	 368.7,	0 },
-	{ 'D',	"Digit 13",	 339.9,	0 },
-	{ 'E',	"Digit 14",	 313.3,	0 },
+	{ 'A',	"Spare 1",	 433.9,	0 },
+	{ 'B',	"Spare 2",	 400.0,	0 },
+	{ 'C',	"Spare 3",	 368.7,	0 },
+	{ 'D',	"Spare 4",	 339.9,	0 },
+	{ 'E',	"Spare 5",	 313.3,	0 },
 	{ '\0',	NULL,		 0.0,	0 },
 };
 

src/eurosignal/eurosignal.c

@@ -422,9 +422,13 @@ void euro_get_id(euro_t *euro, char *id)
 	}
 
 encode:
-	/* return station ID with repeat digit */
-	for (i = 1; i < 6; i++) {
-		if (id[i - 1] == id[i])
+	/* return station ID (upper case) with repeat digit, when required */
+	for (i = 0; i < 6; i++) {
+		/* to upper case */
+		if (id[i] >= 'a' && id[i] <= 'z')
+			id[i] = id[i] - 'a' + 'A';
+		/* repeat digit */
+		if (i && id[i - 1] == id[i])
 			id[i] = 'R';
 	}
 }
@@ -687,7 +691,9 @@ inval:
 		return -CAUSE_INVALNUMBER;
 	}
 	for (i = 0; i < 6; i++) {
-		if (dialing[i] < '0' || dialing[i] > '9')
+		if (!(dialing[i] >= '0' && dialing[i] <= '9')
+		 && !(dialing[i] >= 'a' && dialing[i] <= 'e')
+		 && !(dialing[i] >= 'A' && dialing[i] <= 'E'))
 			goto inval;
 	}