diff options
Diffstat (limited to 'reference/C/CONTRIB/SNIP/morse.c')
| -rwxr-xr-x | reference/C/CONTRIB/SNIP/morse.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/reference/C/CONTRIB/SNIP/morse.c b/reference/C/CONTRIB/SNIP/morse.c new file mode 100755 index 0000000..a280343 --- /dev/null +++ b/reference/C/CONTRIB/SNIP/morse.c @@ -0,0 +1,238 @@ +/*
+** <<< Morse Code Functions >>>
+**
+** Written by Michael M. Dodd, N4CF, and placed in the public domain.
+**
+** The morse() function transmits a string in Morse code on the IBM PC's
+** speaker. The speed is set by a program constant (UNIT_TIME).
+**
+** There are several other functions in this file, all used by morse(),
+** and defined ahead of morse() for convenience.
+**
+** The main() function at the end of the file is a test program to send
+** the command-line argument string in morse code. Enclose multiple
+** words in quotes. Example: morse "hello, world"
+**
+** These functions have been compiled and tested in the Small and Large
+** memory models using Microsoft C 6.00a.
+**
+** Modified for ZTC++, TC++, & BC++ by Bob Stout
+*/
+
+#include <stdio.h>
+#include <dos.h>
+#include <conio.h>
+#include <ctype.h>
+
+/*
+** These functions turn on and off the CW tone on the PC's speaker. The
+** frequency is specified by the freq argument.
+** IMPORTANT! These functions are highly IBM PC-specific!
+*/
+
+#define CLK_FREQ (1193180L)
+#define PIO (0x61)
+#define CTC_CMD (0x43)
+#define CTC_DATA (0x42)
+#define SETUP (0xB6)
+#define TONE_ON (0x03)
+#define TONE_OFF (0xFC)
+
+void note_on (int freq) /* Turn on the tone. */
+{
+ int divisor ;
+ int pio_word ;
+
+ divisor = (int)(CLK_FREQ / (long)(freq)) ;
+ outp (CTC_CMD, SETUP) ;
+ outp (CTC_DATA, divisor & 0xFF) ;
+ outp (CTC_DATA, divisor >> 8) ;
+ pio_word = inp (PIO) ;
+ outp (PIO, pio_word | TONE_ON) ;
+}
+
+void note_off (void) /* Turn off the tone. */
+{
+ int pio_word ;
+
+ pio_word = inp (PIO) ;
+ outp (PIO, pio_word & TONE_OFF) ;
+}
+
+/*
+** These functions implement a timing-loop delay. Because the PC's
+** internal clock is too coarse for accurate CW timing, the pause()
+** function uses a simple software loop to produce a delay.
+**
+** To minimize the effects of CPU clock speed, the calib() function
+** returns a number which represents a rough index of the clock speed
+** with relation to the standard IBM PC (this is very approximate).
+**
+** Calibration is performed only once, when the static fudge_factor is
+** zero. Thereafter, the contents of fudge_factor are used to form a
+** delay value.
+**
+** IMPORTANT! These functions are highly IBM PC-specific!
+*/
+
+unsigned int calib (void)
+{
+ unsigned int far *timerLow = (unsigned int far *)(0x046c) ;
+ unsigned int lastTime ;
+ unsigned int iter ;
+
+ for (lastTime = *timerLow; lastTime == *timerLow;)
+ ;
+
+ for (iter = 0, lastTime = *timerLow; lastTime == *timerLow; iter++)
+ ;
+#if defined(__ZTC__)
+ return ((unsigned int)((125L * ((long)(iter)) + 50L) / 2300L)) ;
+#elif defined(__TURBOC__)
+ return ((unsigned int)((77L * ((long)(iter)) + 50L) / 2300L)) ;
+#else /* assume MSC */
+ return ((unsigned int)((100L * ((long)(iter)) + 50L) / 2300L)) ;
+#endif
+}
+
+void pause (unsigned int amount)
+{
+ static unsigned int fudge_factor = 0 ;
+ unsigned long ul ;
+
+ if (fudge_factor == 0) /* Calibrate the speed. */
+ fudge_factor = calib () ;
+
+ ul = (unsigned long)(amount) * (long)(fudge_factor) ;
+ while (ul--) /* Delay. */
+ ;
+}
+
+/*
+** These functions transmit a dot, a dash, a letter space, and a
+** word space.
+**
+** Note that a single unit space is automatically transmitted after
+** each dot or dash, so the ltr_space() function produces only a
+** two-unit pause.
+**
+** Also, the word_space() function produces only a four-unit pause
+** because the three-unit letter space has already occurred following
+** the previous letter.
+*/
+
+#define SPACE_MASK (1 << 15)
+#define BIT_MASK (0xfe)
+#define UNIT_TIME (18)
+#define FREQUENCY (1500)
+
+void send_dot (void) /* Send a dot and a space. */
+{
+ note_on (FREQUENCY) ;
+ pause (UNIT_TIME) ;
+ note_off () ;
+ pause (UNIT_TIME) ;
+}
+
+void send_dash (void) /* Send a dash and a space. */
+{
+ note_on (FREQUENCY) ;
+ pause (UNIT_TIME * 3) ;
+ note_off () ;
+ pause (UNIT_TIME) ;
+}
+
+void ltr_space (void) /* Produce a letter space. */
+{
+ pause (UNIT_TIME * 2) ;
+}
+
+void word_space (void) /* Produce a word space. */
+{
+ pause (UNIT_TIME * 4) ;
+}
+
+
+/*
+** MORSE () - Transmit a string in Morse code
+**
+** This function transmits the string pointed to by the cp argument in
+** Morse code on the PC's speaker. The speed is set by the UNIT_TIME
+** constant.
+**
+** A static table translates from ASCII to Morse code. Each entry is
+** an unsigned integer, where a zero represents a dot and a one
+** represents a dash. No more than 14 bits may be used. Setting bit
+** 15 produces a word space, regardless of any other pattern.
+**
+** The Morse code pattern is taken from bit 0, and is shifted right
+** each time an element is sent. A special "marker bit" follows the
+** complete Morse pattern. This marker bit is tested before
+** transmitting each bit; if there are no 1's in bits 1..15, the
+** complete character has been sent.
+**
+** For example, an "L" would be 0000000000010010, with bit zero
+** containing the first dot, bit one the dash, etc. The marker
+** bit is in bit 4.
+*/
+
+void morse (char *cp)
+{ /*--- MORSE CODE FUNCTION ---*/
+
+ unsigned int c ;
+ static unsigned int codes [64] = {
+ SPACE_MASK, /* Entry 0 = space (0x20) */
+ 0, 0, 0, 0, 0, 0, 0, 0, /* ! " # $ % & " ( */
+ 0, 0, 0, 115, 49, 106, 41, /* ) * + , - . / */
+ 63, 62, 60, 56, 48, 32, 33, 35, /* 0 1 2 3 4 5 6 7 */
+ 39, 47, 0, 0, 0, 0, 0, 76, /* 8 9 : ; < = > ? */
+ 0, 6, 17, 21, 9, 2, 20, 11, /* @ A B C D E F G */
+ 16, 4, 30, 13, 18, 7, 5, 15, /* H I J K L M N O */
+ 22, 27, 10, 8, 3, 12, 24, 14, /* P Q R S T U V W */
+ 25, 29, 19 /* X Y Z */
+ } ;
+
+ pause (0) ; /* Calibrate pause() function. */
+
+ while ((c = *cp++) != '\0')
+ { /*--- TRANSMIT COMPLETE STRING ---*/
+
+ c = toupper (c) ; /* No lower-case Morse characters. */
+ c -= ' ' ; /* Adjust for zero-based table. */
+
+ if (c < 0 || c > 58) /* If out of range, ignore it. */
+ continue ;
+
+ c = codes[c] ; /* Look up Morse pattern from table. */
+
+ if (c & SPACE_MASK) /* If the space bit is set.. */
+ { /* ..send a word space and go on. */
+ word_space () ;
+ continue ;
+ }
+
+ while (c & BIT_MASK) /* Transmit one character. */
+ { /*--- TRANSMIT EACH BIT ---*/
+ if (c & 1)
+ send_dash () ;
+ else send_dot () ;
+
+ c >>= 1 ;
+ } /*--- TRANSMIT EACH BIT ---*/
+
+ ltr_space () ; /* Send a space following character. */
+
+ } /*--- TRANSMIT COMPLETE STRING ---*/
+
+} /*--- MORSE CODE FUNCTION ---*/
+
+
+/*
+** This is the test program, which transmits argv[1] in Morse code.
+*/
+
+void main (int argc, char *argv[])
+{
+ if (argc > 1)
+ morse (argv[1]) ;
+}
|