diff --git a/12hourclk.c b/12hourclk.c
index f8e9ee9..0419e62 100644
--- a/12hourclk.c
+++ b/12hourclk.c
@@ -1,7 +1,20 @@
 #include <stdio.h>      /* printf, scanf */
+#include <stdbool.h>    /* bool */
+#include <string.h>     /* strerror */
+#include <time.h>       /* time_t, time, localtime */
 #include <ctype.h>      /* toupper */
+#include <errno.h>      /* errno */
+
 #include "12hourclk.h"
 
+#define TIME_ERR_RESULT         ((time_t) -1)
+#define LOCALTIME_ERR_RESULT    NULL
+#define ERR_MSG_SIZE            128
+
+static void set_err_msg(char *prefix, int errno);
+
+static char G_err_msg[ERR_MSG_SIZE];
+
 static char *meridiem_text(meridiem_t m)
 {
     if (m == ANTE_MERIDIEM) {
@@ -12,6 +25,49 @@ static char *meridiem_text(meridiem_t m)
     }
 }
 
+bool set_clock(twleve_hour_clock_t *clock, struct tm *t)
+{
+    clock->seconds = t->tm_sec;
+    clock->minutes = t->tm_min;
+    if (t->tm_hour == 0) {
+        clock->hours = 12;
+        clock->meridiem = ANTE_MERIDIEM;
+    }
+    else if (t->tm_hour < 12) {
+        clock->meridiem = ANTE_MERIDIEM;
+    }
+    else if (t->tm_hour == 12) {
+        clock->meridiem = POST_MERIDIEM;
+    }
+    else {
+        clock->hours = t->tm_hour - 12;
+        clock->meridiem = POST_MERIDIEM;
+    }
+    return true;
+}
+
+
+void set_err_msg(char *what_failed, int err_code)
+{
+    snprintf(G_err_msg, ERR_MSG_SIZE, "%s: %s", what_failed, strerror(err_code));
+}
+
+bool load_system_time(twleve_hour_clock_t *clock)
+{
+    time_t now;
+    bool is_successful = false; /* It will not be successful until it is. */
+    struct tm *curr_time;
+
+    if (time(&now) != TIME_ERR_RESULT)
+        if ((curr_time = localtime(&now)) != LOCALTIME_ERR_RESULT)
+            is_successful = set_clock(clock, curr_time);
+        else 
+            set_err_msg("Localtime function failed", errno);
+    else
+        set_err_msg("Time function failed", errno);
+    return is_successful;
+}
+
 void read_interactively(twleve_hour_clock_t *clock)
 {
     char meridiem_input[3];
diff --git a/12hourclk.h b/12hourclk.h
index 44b2ba5..ae35e32 100644
--- a/12hourclk.h
+++ b/12hourclk.h
@@ -15,6 +15,7 @@ typedef struct {
 } twleve_hour_clock_t;
 
 extern void read_interactively(twleve_hour_clock_t *clock);
+extern bool load_system_time(twleve_hour_clock_t *clock);
 extern void add_one_second(twleve_hour_clock_t *clock);
 extern void add_seconds(twleve_hour_clock_t *clock, uint8_t seconds);
 extern void print_time(twleve_hour_clock_t *clock);
diff --git a/Makefile b/Makefile
index 51583c8..a5f92d8 100644
--- a/Makefile
+++ b/Makefile
@@ -13,17 +13,18 @@ endif
 PGM=alarmclk
 OBJS=alarmclk.o 12hourclk.o clkfreq.o
 
-PGM2=cpufreq
-OBJS2=clkfreq.o
+PGM2=calibrate
+OBJS2=calibrate.o
 
 CC=cl65
 AS=ca65
+LD=ld65
 
 CFLAGS=-t $(CC65_TARGET) -O
 ASFLAGS=-t $(CC65_TARGET)
 LDFLAGS=-t $(CC65_TARGET)
 
-DISK_VOL=ALARMCLK
+DISK_VOL=alarmclk
 DISK=$(DISK_VOL).dsk
 
 AC=java -jar lib/AppleCommander-1.3.5.14.jar
@@ -36,12 +37,14 @@ all: $(DISK)
 $(DISK): $(PGM) $(PGM2)
 	$(AC) -d $(DISK) $<
 	$(AC) -cc65 $(DISK) $< BIN < $<
+	$(AC) -d $(DISK) $(PGM2)
+	$(AC) -cc65 $(DISK) $(PGM2) BIN < $(PGM2)
 
 $(PGM): $(OBJS)
 	$(CC) $(LDFLAGS) -o $@ $^
 
-$(PGM2): clkfreq.s
-	$(AS) $(ASFLAGS) -o $@ $^
+$(PGM2): $(OBJS2)
+	$(CC) $(LDFLAGS) -o $@ $^
 
 # Compile and assemble rules use the defuault rules after CC and CFLAGS
 # are set.
diff --git a/alarmclk.c b/alarmclk.c
index 23f4ad5..cea6020 100644
--- a/alarmclk.c
+++ b/alarmclk.c
@@ -5,8 +5,8 @@
 #include <conio.h>      /* clrscr, kbhit */
 
 #include "12hourclk.h"
-extern void clkfreq();
-extern uint8_t ticks[4];
+extern void ClockFreq();
+extern uint8_t Ticks[4];
 
 #define CLOCK_FREQUENCY 1023000L
 #define CYCLES_PER_NOOP 2
@@ -23,17 +23,18 @@ static twleve_hour_clock_t alarm_time;
 
 void main(void)
 {
-    clkfreq();
+    ClockFreq();
     printf("%c%c.%c%c%c%c%c%c MHz\n", 
-        ticks[0] & 0x70,
-        ticks[0] & 0x07,
-        ticks[1] & 0x70,
-        ticks[1] & 0x07,
-        ticks[2] & 0x70,
-        ticks[2] & 0x07,
-        ticks[3] & 0x70,
-        ticks[3] & 0x07);
+        Ticks[0] & 0x70,
+        Ticks[0] & 0x07,
+        Ticks[1] & 0x70,
+        Ticks[1] & 0x07,
+        Ticks[2] & 0x70,
+        Ticks[2] & 0x07,
+        Ticks[3] & 0x70,
+        Ticks[3] & 0x07);
 
+    clrscr();
     read_inputs();
 
     clrscr();
@@ -46,8 +47,10 @@ void main(void)
 
 void read_inputs()
 {
-    puts("Current Time");
-    read_interactively(&curr_time);
+    if (! load_system_time(&curr_time)) {
+        puts("Current Time");
+        read_interactively(&curr_time);
+    }
     puts("Alarm Time");
     read_interactively(&alarm_time);
 }
diff --git a/alarmclk.dsk b/alarmclk.dsk
new file mode 100644
index 0000000..de3662d
Binary files /dev/null and b/alarmclk.dsk differ
diff --git a/alarmclk.s b/alarmclk.s
new file mode 100644
index 0000000..992ca52
--- /dev/null
+++ b/alarmclk.s
@@ -0,0 +1,515 @@
+;
+; File generated by cc65 v 2.15 - Git 6f24c07
+;
+	.fopt		compiler,"cc65 v 2.15 - Git 6f24c07"
+	.setcpu		"65C02"
+	.smart		on
+	.autoimport	on
+	.case		on
+	.debuginfo	off
+	.importzp	sp, sreg, regsave, regbank
+	.importzp	tmp1, tmp2, tmp3, tmp4, ptr1, ptr2, ptr3, ptr4
+	.macpack	longbranch
+	.forceimport	__STARTUP__
+	.import		_printf
+	.import		_puts
+	.import		_toupper
+	.import		_clrscr
+	.import		_kbhit
+	.import		_cgetc
+	.import		_read_interactively
+	.import		_load_system_time
+	.import		_add_one_second
+	.import		_print_time
+	.import		_reprint_time
+	.import		_ClockFreq
+	.import		_Ticks
+	.export		_read_inputs
+	.export		_elapse_one_second
+	.export		_run_clock
+	.export		_main
+
+.segment	"RODATA"
+
+L0009:
+	.byte	$25,$63,$25,$63,$2E,$25,$63,$25,$63,$25,$63,$25,$63,$25,$63,$25
+	.byte	$63,$20,$4D,$48,$7A,$0A,$00
+L001F:
+	.byte	$0A,$41,$6C,$61,$72,$6D,$20,$54,$69,$6D,$65,$3A,$20,$20,$20,$00
+L0024:
+	.byte	$0A,$43,$75,$72,$72,$65,$6E,$74,$20,$54,$69,$6D,$65,$3A,$20,$00
+L002C:
+	.byte	$43,$75,$72,$72,$65,$6E,$74,$20,$54,$69,$6D,$65,$00
+L0031:
+	.byte	$41,$6C,$61,$72,$6D,$20,$54,$69,$6D,$65,$00
+L004B	:=	L0009+22
+
+.segment	"BSS"
+
+_curr_time:
+	.res	5,$00
+_alarm_time:
+	.res	5,$00
+
+; ---------------------------------------------------------------
+; void __near__ read_inputs (void)
+; ---------------------------------------------------------------
+
+.segment	"CODE"
+
+.proc	_read_inputs: near
+
+.segment	"CODE"
+
+	lda     #<(_curr_time)
+	ldx     #>(_curr_time)
+	jsr     _load_system_time
+	jsr     bnega
+	jeq     L0028
+	lda     #<(L002C)
+	ldx     #>(L002C)
+	jsr     _puts
+	lda     #<(_curr_time)
+	ldx     #>(_curr_time)
+	jsr     _read_interactively
+L0028:	lda     #<(L0031)
+	ldx     #>(L0031)
+	jsr     _puts
+	lda     #<(_alarm_time)
+	ldx     #>(_alarm_time)
+	jsr     _read_interactively
+	rts
+
+.endproc
+
+; ---------------------------------------------------------------
+; void __near__ elapse_one_second (void)
+; ---------------------------------------------------------------
+
+.segment	"CODE"
+
+.proc	_elapse_one_second: near
+
+.segment	"CODE"
+
+	jsr     decsp4
+	ldx     #$07
+	lda     #$FE
+	ldy     #$00
+	jsr     staxysp
+	ldx     #$00
+	lda     #$00
+	ldy     #$02
+	jsr     staxysp
+L0050:	ldy     #$03
+	jsr     ldaxysp
+	jsr     pushax
+	ldy     #$03
+	jsr     ldaxysp
+	jsr     tosltax
+	jne     L0053
+	jmp     L0051
+L0053:	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	ldy     #$02
+	ldx     #$00
+	lda     #$01
+	jsr     addeqysp
+	jmp     L0050
+L0051:	jsr     incsp4
+	rts
+
+.endproc
+
+; ---------------------------------------------------------------
+; void __near__ run_clock (void)
+; ---------------------------------------------------------------
+
+.segment	"CODE"
+
+.proc	_run_clock: near
+
+.segment	"CODE"
+
+	jsr     decsp1
+	lda     #<(_curr_time)
+	ldx     #>(_curr_time)
+	jsr     _print_time
+	jmp     L003A
+L0038:	jsr     _elapse_one_second
+	lda     #<(_curr_time)
+	ldx     #>(_curr_time)
+	jsr     _add_one_second
+	lda     #<(_curr_time)
+	ldx     #>(_curr_time)
+	jsr     _reprint_time
+	jsr     _kbhit
+	tax
+	jeq     L003A
+	jsr     _cgetc
+	ldy     #$00
+	sta     (sp),y
+	ldy     #$00
+	ldx     #$00
+	lda     (sp),y
+	cmp     #$1B
+	jsr     booleq
+	jne     L0046
+	ldy     #$00
+	ldx     #$00
+	lda     (sp),y
+	ldx     #$00
+	jsr     _toupper
+	cpx     #$00
+	bne     L0048
+	cmp     #$51
+L0048:	jsr     booleq
+	jne     L0046
+	ldy     #$00
+	ldx     #$00
+	lda     (sp),y
+	cmp     #$03
+	jsr     booleq
+	jne     L0046
+	ldx     #$00
+	lda     #$00
+	jeq     L0049
+L0046:	ldx     #$00
+	lda     #$01
+L0049:	jeq     L003A
+	lda     #<(L004B)
+	ldx     #>(L004B)
+	jsr     _puts
+	jmp     L0039
+L003A:	jmp     L0038
+L0039:	jsr     incsp1
+	rts
+
+.endproc
+
+; ---------------------------------------------------------------
+; void __near__ main (void)
+; ---------------------------------------------------------------
+
+.segment	"CODE"
+
+.proc	_main: near
+
+.segment	"CODE"
+
+	ldy     #$00
+	jsr     _ClockFreq
+	lda     #<(L0009)
+	ldx     #>(L0009)
+	jsr     pushax
+	ldx     #$00
+	lda     _Ticks
+	ldx     #$00
+	and     #$70
+	jsr     pushax
+	ldx     #$00
+	lda     _Ticks
+	ldx     #$00
+	and     #$07
+	jsr     pushax
+	ldx     #$00
+	lda     _Ticks+1
+	ldx     #$00
+	and     #$70
+	jsr     pushax
+	ldx     #$00
+	lda     _Ticks+1
+	ldx     #$00
+	and     #$07
+	jsr     pushax
+	ldx     #$00
+	lda     _Ticks+2
+	ldx     #$00
+	and     #$70
+	jsr     pushax
+	ldx     #$00
+	lda     _Ticks+2
+	ldx     #$00
+	and     #$07
+	jsr     pushax
+	ldx     #$00
+	lda     _Ticks+3
+	ldx     #$00
+	and     #$70
+	jsr     pushax
+	ldx     #$00
+	lda     _Ticks+3
+	ldx     #$00
+	and     #$07
+	jsr     pushax
+	ldy     #$12
+	jsr     _printf
+	jsr     _clrscr
+	jsr     _read_inputs
+	jsr     _clrscr
+	lda     #<(L001F)
+	ldx     #>(L001F)
+	jsr     pushax
+	ldy     #$02
+	jsr     _printf
+	lda     #<(_alarm_time)
+	ldx     #>(_alarm_time)
+	jsr     _print_time
+	lda     #<(L0024)
+	ldx     #>(L0024)
+	jsr     pushax
+	ldy     #$02
+	jsr     _printf
+	jsr     _run_clock
+	rts
+
+.endproc
+
diff --git a/calcClkfreq.c b/calcClkfreq.c
new file mode 100644
index 0000000..b637092
--- /dev/null
+++ b/calcClkfreq.c
@@ -0,0 +1,9 @@
+/* This file is only here to make clkfreq.s load successfully. */
+
+#include "clkfreq.h"
+
+void main()
+{
+    clkfreq();
+}
+
diff --git a/calibrate.s b/calibrate.s
new file mode 100644
index 0000000..f07f647
--- /dev/null
+++ b/calibrate.s
@@ -0,0 +1,93 @@
+.forceimport	__STARTUP__
+.export         _main
+
+.segment    "RODATA"
+
+; All numbers are going to be this size and type.
+Unsigned_Integer_Size = 4
+; Standard character output routine
+COUT = $fded
+
+.segment    "BSS"
+
+Sleep_Loop_Count: .res Unsigned_Integer_Size,0 ; Byte values initialized to 0
+
+; *************************************
+;
+;   Macros
+;
+; *************************************
+
+; Number++
+.macro Increment Number
+    .local Next_Byte
+    .local Done
+    ldx #0                      ; X := 0
+Next_Byte:
+    inc Number,X                ; Increment the value at Count+X address
+    bne Done                    ; Incrementing Count did not cause it to roll over to 0.
+    inx                         ; Increment X to the next byte
+    cpx #Unsigned_Integer_Size  ; Compare X with 4.
+    bmi Next_Byte               ; If X < Count_Size continue with next byte.
+Done:
+.endmacro
+
+; Minuend = Minuend - Subtrahend
+.macro Subtract Minuend, Subtrahend
+    .local Next_Byte
+    ldx #0
+    clc
+Next_Byte:
+    lda Addr1,X
+    sbc Addr2,X
+    inx
+    cpx #Unsigned_Integer_Size
+    bmi Next_Byte
+.endmacro
+
+; *************************************
+;
+;   Main
+;
+; *************************************
+
+.segment    "CODE"
+
+.proc   _main:  near
+
+.segment    "CODE"
+
+Sleep_Loop:
+
+; Do nothing 10 times.
+
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+    nop
+
+    Increment Sleep_Loop_Count
+    lda #1
+    cmp Sleep_Loop_Count+3
+    bmi Sleep_Loop
+
+; Output result
+
+    ldx #0
+Next_Byte:
+    lda Sleep_Loop_Count,X
+    jsr COUT
+    inx
+    cpx #Unsigned_Integer_Size
+    bmi Next_Byte
+
+    rts ; from _main
+
+.endproc
+
diff --git a/clkfreq b/clkfreq
new file mode 100644
index 0000000..36ea607
Binary files /dev/null and b/clkfreq differ
diff --git a/clkfreq.h b/clkfreq.h
new file mode 100644
index 0000000..70c3545
--- /dev/null
+++ b/clkfreq.h
@@ -0,0 +1,10 @@
+#ifndef CLKFREQ_H
+#define CLKFREQ_H
+
+#include <stdint.h> /* uint8_t */
+
+extern void clkfreq(void);
+extern uint8_t ticks[4];
+
+#endif
+
diff --git a/clkfreq.s b/clkfreq.s
index 470e928..a41a8ae 100644
--- a/clkfreq.s
+++ b/clkfreq.s
@@ -1,3 +1,18 @@
+	.setcpu		"65C02"
+	.smart		on
+	.autoimport	on
+	.case		on
+	.debuginfo	off
+	.importzp	sp, sreg, regsave, regbank
+	.importzp	tmp1, tmp2, tmp3, tmp4, ptr1, ptr2, ptr3, ptr4
+	.macpack	longbranch
+	.forceimport	__STARTUP__
+        .import         _fputc
+        .import         _stdout
+
+        .export         _Ticks
+        .export         _ClockFreq
+
 rgConfig        =       $6000   ; write: D6=1 - NMI is off, D6=0 - NMI is on
 rgStatus        =       $6000   ; read:  D6=0 - UART is busy
 rgTxD           =       $5000   ; write: data to send via UART
@@ -6,9 +21,12 @@ vcNMI           =       $FFFA
 
 Refresh         =       450     ; NMI rate in Hz
 
-.export _clkfreq
-.export _ticks
-_clkfreq:
+.segment	"CODE"
+
+.proc	_ClockFreq: near
+
+.segment	"CODE"
+
         ldx     #<NMI           ; installing the NMI vector
         ldy     #>NMI
         stx     vcNMI
@@ -19,10 +37,10 @@ _clkfreq:
 Again:
         lda     #0
         sta     Flag
-        sta     _ticks          ; initializing counter
-        sta     _ticks+1
-        sta     _ticks+2
-        sta     _ticks+3
+        sta     _Ticks          ; initializing counter
+        sta     _Ticks+1
+        sta     _Ticks+2
+        sta     _Ticks+3
         lda     #$FE            ; initializing NMI counter (zeropoint minus 2 ticks)
         sta     Timer
         lda     #$FF
@@ -45,40 +63,40 @@ L2:     bit     Flag            ; waiting for true zeropoint
 Main:                           ; main counting cycle
 ;number of ticks per command   sum of ticks
 ;                          v   v
-        lda     _ticks     ;4
+        lda     _Ticks    ;4
         clc               ;2   6
         sed               ;2   8
         adc     #$53      ;2  10
-        sta     _ticks     ;4  14
-        lda     _ticks+1   ;4  18
+        sta     _Ticks    ;4  14
+        lda     _Ticks+1  ;4  18
         adc     #0        ;2  20
-        sta     _ticks+1   ;4  24
-        lda     _ticks+2   ;4  28
+        sta     _Ticks+1  ;4  24
+        lda     _Ticks+2  ;4  28
         adc     #0        ;2  30
-        sta     _ticks+2   ;4  34
-        lda     _ticks+3   ;4  38
+        sta     _Ticks+2  ;4  34
+        lda     _Ticks+3  ;4  38
         adc     #0        ;2  40
-        sta     _ticks+3   ;4  44
+        sta     _Ticks+3  ;4  44
         cld               ;2  46
         bit     Flag      ;4  50
         bpl     Main      ;3  53
 
         lda     #0        ;2
         sta     Flag      ;4   6
-        lda     _ticks     ;4  10
+        lda     _Ticks    ;4  10
         clc               ;2  12
         sed               ;2  14
         adc     #$95      ;2  16
-        sta     _ticks     ;4  20
-        lda     _ticks+1   ;4  24
+        sta     _Ticks    ;4  20
+        lda     _Ticks+1  ;4  24
         adc     #0        ;2  26
-        sta     _ticks+1   ;4  30
-        lda     _ticks+2   ;4  34
+        sta     _Ticks+1  ;4  30
+        lda     _Ticks+2  ;4  34
         adc     #0        ;2  36
-        sta     _ticks+2   ;4  40
-        lda     _ticks+3   ;4  44
+        sta     _Ticks+2  ;4  40
+        lda     _Ticks+3  ;4  44
         adc     #0        ;2  46
-        sta     _ticks+3   ;4  50
+        sta     _Ticks+3  ;4  50
         cld               ;2  52
         lda     Timer     ;4  56
         cmp     #<Refresh ;2  58
@@ -92,14 +110,16 @@ Main:                           ; main counting cycle
         sta     rgConfig
         sta     InUse
 
+; Output
+
         ldx     #0              ; send first string to the host
 L3:     lda     Mes1,x
         beq     L4
-        jsr     Send
+        jsr     PutChar
         inx
         jmp     L3
 
-L4:     lda     _ticks+3
+L4:     lda     _Ticks+3
         pha
         lsr
         lsr
@@ -111,21 +131,24 @@ L5:     pla
         and     #15
         jsr     PrintDigit
         lda     #'.'            ; decimal point
-        jsr     Send
-        lda     _ticks+2
+        jsr     PutChar
+        lda     _Ticks+2
         jsr     PrintTwoDigits
-        lda     _ticks+1
+        lda     _Ticks+1
         jsr     PrintTwoDigits
-        lda     _ticks
+        lda     _Ticks
         jsr     PrintTwoDigits
 
         ldx     #0              ; send second string to the host
 L6:     lda     Mes2,x
         beq     L7
-        jsr     Send
+        jsr     PutChar
         inx
         jmp     L6
-L7:     jmp     Again           ; repeat process
+L7:
+        rts
+
+.endproc
 
 PrintTwoDigits:
         pha
@@ -141,15 +164,26 @@ PrintTwoDigits:
 
 PrintDigit:
         ora     #$30
-        jsr     Send
+        jsr     PutChar
         rts
 
+PutChar:
+; The character should be in the Accumulator
+	ldx     #$00
+	jsr     pushax
+	lda     _stdout
+	ldx     _stdout+1
+	jsr     _fputc
+	rts
+
 Send:
         bit     rgStatus
         bvc     Send
         sta     rgTxD
         rts
 
+.segment    "RODATA"
+
 Mes1:
         .byte   13
         .byte   "Current clock frequency is "
@@ -159,11 +193,19 @@ Mes2:
         .byte   " MHz"
         .byte   0
 
-_ticks:  .res    4,0
-Timer:  .res    2,0
-InUse:  .byte   0
-Flag:   .byte   0
+.segment    "DATA"
 
+_Ticks: .res    4,0     ; uint8_t   _Ticks[4]
+Timer:  .res    2,0     ; uint16_t  Timer
+InUse:  .byte   0       ; uint8_t   InUse
+Flag:   .byte   0       ; uint8_t   Flag
+
+.segment    "CODE"
+
+; Called when an non-maskable interrupt occurs.
+; 1. Increments Timer
+; 2. Sets the high bit in Flag to 1
+;
 NMI:                       ;6
         pha                ;3   9
         inc     Timer      ;6  15
@@ -173,3 +215,4 @@ L8:     lda     #$80       ;2  20
         sta     Flag       ;4  24
         pla                ;4  28
         rti                ;6  34
+
diff --git a/printf.s b/printf.s
new file mode 100644
index 0000000..0f3526c
--- /dev/null
+++ b/printf.s
@@ -0,0 +1,37 @@
+;
+; File generated by cc65 v 2.15 - Git 6f24c07
+;
+	.fopt		compiler,"cc65 v 2.15 - Git 6f24c07"
+	.setcpu		"65C02"
+	.smart		on
+	.autoimport	on
+	.case		on
+	.debuginfo	off
+	.importzp	sp, sreg, regsave, regbank
+	.importzp	tmp1, tmp2, tmp3, tmp4, ptr1, ptr2, ptr3, ptr4
+	.macpack	longbranch
+	.forceimport	__STARTUP__
+	.import		_stdout
+	.import		_fputc
+	.export		_main
+
+; ---------------------------------------------------------------
+; void __near__ main (void)
+; ---------------------------------------------------------------
+
+.segment	"CODE"
+
+.proc	_main: near
+
+.segment	"CODE"
+
+	ldx     #$00
+	lda     #$41
+	jsr     pushax
+	lda     _stdout
+	ldx     _stdout+1
+	jsr     _fputc
+	rts
+
+.endproc
+
diff --git a/putc.c b/putc.c
new file mode 100644
index 0000000..29fbf23
--- /dev/null
+++ b/putc.c
@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+void main(void)
+{
+    putc('A', stdout);
+}
diff --git a/putc.s b/putc.s
new file mode 100644
index 0000000..54eae22
--- /dev/null
+++ b/putc.s
@@ -0,0 +1,25 @@
+	.file	"putc.c"
+	.text
+	.globl	main
+	.type	main, @function
+main:
+.LFB0:
+	.cfi_startproc
+	pushq	%rbp
+	.cfi_def_cfa_offset 16
+	.cfi_offset 6, -16
+	movq	%rsp, %rbp
+	.cfi_def_cfa_register 6
+	movq	stdout(%rip), %rax
+	movq	%rax, %rsi
+	movl	$65, %edi
+	call	_IO_putc
+	nop
+	popq	%rbp
+	.cfi_def_cfa 7, 8
+	ret
+	.cfi_endproc
+.LFE0:
+	.size	main, .-main
+	.ident	"GCC: (GNU) 5.1.1 20150618 (Red Hat 5.1.1-4)"
+	.section	.note.GNU-stack,"",@progbits