CS2771/assignments/alarm: Initial commit

2 files changed, 90 insertions, 0 deletions

diff --git a/alarm/alarm.asm b/alarm/alarm.asm
new file mode 100644
index 0000000..dd094ed
--- /dev/null
+++ b/alarm/alarm.asm
@@ -0,0 +1,65 @@
+;
+;30h-39h hold the 7seg bit patterns
+	mov	30h, #11000000B
+	mov	31h, #11111001B
+	mov 32h, #10100100B
+	mov	33h, #10110000B
+	mov 34h, #10011001B
+	mov	35h, #10010010B
+	mov 36h, #10000010B
+	mov 37h, #10000111B
+	mov 38h, #10000000B
+	mov 39h, #10011000B
+
+	mov 
+start:
+	
+	
+
+jmp start
+;40h-42h hold the 3 digits to display
+	
+display:
+	mov	acc, 50h
+	mov 	b,	#1000
+	div ab
+	mov 40h, acc
+	mov acc, b
+	mov	b, #100
+	div ab
+	mov	41h, acc; save 100's digit
+	mov	acc, b   ;put remainder in a
+	mov	b, #10  ;find 10's & 1's digit
+	div ab
+	mov	42h, acc  ;save 10's digit
+	mov	43h, b  ;save 1's digit
+
+
+
+;display:
+	mov	r1, #40h ;digits[0]
+
+loop:  ;for each digit
+	mov	acc, #30h
+	mov r3, acc  ;save acc;next blob:
+
+;safe if you don't care about the
+;bits of P3 other than p3.3 & p3.4
+	mov	a, r1    ;picks which
+	cpl a        ;7seg to use p3.3 &
+	anl	a, #03h  ;p3.4 are a func
+	rl	a        ;of the low2 bits of
+	rl	a        ;the addr where the
+	rl	a        ;digits live
+	mov	p1, #0ffh;undraw previous
+	mov	p3, a	 ;set new 7seg
+	mov	a, r3    ;restore acc
+
+; p1 = pattern[digit[i]] 
+	add	a, @r1
+	mov	r0, acc
+	mov	p1, @r0
+	inc	r1
+;	mov	p1, #0ffh
+	cjne	r1, #44h, loop
+	ret
diff --git a/alarm/assign.rst b/alarm/assign.rst
new file mode 100644
index 0000000..f9c802a
--- /dev/null
+++ b/alarm/assign.rst
@@ -0,0 +1,25 @@
+===========
+Alarm clock
+===========
+
+Write an 8051 program which implements an alarm clock. This project will
+have two phases, the first of which is described here. The alarm clock
+runs all the time, with the current time displayed on the four 7-segment
+displays. In this first phase your clock needs to:
+  1. use timers to keep time updated to the second
+  2. switch between 12 hour and 24 hour modes based switch bank.0 (0==12
+   hr, 1==24hr)
+  3. if you are in 12 hour mode, use the decimal point on the last
+   7-segment display to indicate AM or PM (off = AM, on == PM)
+  4. switch between display of hours:minutes and minutes:seconds based on
+   switch bank.1 (0==hours:minutes, 1==minutes:seconds)
+  5. keep the decimal point of the second 7-segment display lit as a
+   visual separator
+
+AM/PM should remain indicated regardless of which display mode you are
+using.
+
+You do not (yet) need to be able to:
+  - set the time (pick a starting value)
+  - set an alarm time
+  - perform an alarm