X-Git-Url: http://nitlanguage.org

diff --git a/lib/bcm2835.nit b/lib/bcm2835.nit
index 9de90ff..aac7352 100644
--- a/lib/bcm2835.nit
+++ b/lib/bcm2835.nit
@@ -118,3 +118,455 @@ redef universal Int
 	fun bcm2835_delay `{ bcm2835_delay(recv); `}
 	fun bcm2835_delay_micros `{ bcm2835_delayMicroseconds(recv); `}
 end
+
+class RotaryEncoder
+	var pin_a: RPiPin
+	var pin_b: RPiPin
+	var old_a= false
+	var old_b= false
+
+	# returns '<', '>' or null accoring to rotation or lack thereof
+	fun update: nullable Char
+	do
+		var new_a = pin_a.lev
+		var new_b = pin_b.lev
+		var res = null
+
+		if new_a != old_a or new_b != old_b then
+			if not old_a and not old_b then
+				# everything was on
+				if not new_a and new_b then
+					res = '<'
+				else if new_a and not new_b then
+					res = '>'
+				end
+			else if old_a and old_b then
+				# everything was off
+				if not new_a and new_b then
+					res = '>'
+				else if new_a and not new_b then
+					res = '<'
+				end
+			end
+
+			old_a = new_a
+			old_b = new_b
+		end
+
+		return res
+	end
+end
+
+# Hitachi HD44780 or similar 2-4 lines LCD displays
+class HD44780
+	var rs: RPiPin
+	var en: RPiPin
+	var d4: RPiPin
+	var d5: RPiPin
+	var d6: RPiPin
+	var d7: RPiPin
+
+	var ds = new Array[RPiPin]
+
+	# commands
+	fun flag_clear_display: Int do return 1
+	fun flag_return_home: Int do return 2
+	fun flag_entry_mode_set: Int do return 4
+	fun flag_display_control: Int do return 8
+	fun flag_cursor_shift: Int do return 16
+	fun flag_function_set: Int do return 32
+	fun flag_set_cgram_addr: Int do return 64
+	fun flag_set_ggram_addr: Int do return 128
+
+	# entry mode
+	fun flag_entry_right: Int do return 0
+	fun flag_entry_left: Int do return 2
+	fun flag_entry_shift_increment: Int do return 1
+	fun flag_entry_shift_decrement: Int do return 0
+
+	# display flags
+	fun flag_display_on: Int do return 4
+	fun flag_display_off: Int do return 0
+	fun flag_cursor_on: Int do return 2
+	fun flag_cursor_off: Int do return 0
+	fun flag_blink_on: Int do return 1
+	fun flag_blink_off: Int do return 0
+
+	# display/cursor shift
+	fun flag_display_move: Int do return 8
+	fun flag_cursor_move: Int do return 0
+	fun flag_move_right: Int do return 4
+	fun flag_move_left: Int do return 0
+
+	# function set
+	fun flag_8bit_mode: Int do return 16
+	fun flag_4bit_mode: Int do return 0
+	fun flag_2_lines: Int do return 8
+	fun flag_1_line: Int do return 0
+	fun flag_5x10_dots: Int do return 4
+	fun flag_5x8_dots: Int do return 0
+
+	# last text displayed
+	private var last_text: nullable String = null
+
+	fun function_set(bits, lines, dots_wide: Int)
+	do
+		var fs = flag_function_set
+		if bits == 8 then
+			fs = fs.bin_or(16)
+		else if bits != 4 then abort
+
+		if lines == 2 then
+			fs = fs.bin_or(8)
+		else if lines != 1 then abort
+
+		if dots_wide == 10 then
+			fs = fs.bin_or(4)
+		else if dots_wide != 8 then abort
+
+		write(true, fs)
+	end
+
+	fun display_control(on, cursor, blink: Bool)
+	do
+		var fs = flag_display_control
+
+		if on then
+			fs = fs.bin_or(flag_display_on)
+		else fs = fs.bin_or(flag_display_off)
+
+		if cursor then
+			fs = fs.bin_or(flag_cursor_on)
+		else fs = fs.bin_or(flag_cursor_off)
+
+		if blink then
+			fs = fs.bin_or(flag_blink_on)
+		else fs = fs.bin_or(flag_blink_off)
+
+		write(true, fs)
+	end
+
+	fun entry_mode(left, incr: Bool)
+	do
+		var fs = flag_entry_mode_set
+
+		if left then
+			fs = fs.bin_or(flag_entry_left)
+		else fs = fs.bin_or(flag_entry_right)
+
+		if incr then
+			fs = fs.bin_or(flag_entry_shift_increment)
+		else fs = fs.bin_or(flag_entry_shift_decrement)
+
+		write(true, fs)
+	end
+
+	fun setup_alt
+	do
+		ds = [d4,d5,d6,d7]
+
+		rs.fsel = new FunctionSelect.outp
+		en.fsel = new FunctionSelect.outp
+		d4.fsel = new FunctionSelect.outp
+		d5.fsel = new FunctionSelect.outp
+		d6.fsel = new FunctionSelect.outp
+		d7.fsel = new FunctionSelect.outp
+
+		rs.write(false)
+		en.write(false)
+
+		# wait 20ms for power up
+		50.bcm2835_delay
+
+		write_4bits(true,true,false,false)
+		write_4_bits(3)
+
+		5.bcm2835_delay
+
+		write_4bits(true,true,false,false)
+		write_4_bits(3)
+
+		5.bcm2835_delay
+
+		write_4bits(true,true,false,false)
+		write_4_bits(3)
+
+		200.bcm2835_delay_micros
+
+		write_4bits(false,true,false,false)
+		write_4_bits(2)
+
+		# wait 5ms
+		5.bcm2835_delay
+
+		# set interface
+		# 4bits, 2 lines
+		function_set(4, 2, 8)
+
+		# cursor
+		# don't shift & hide
+		display_control(true, true, true)
+
+		# clear & home
+		clear
+
+		# set cursor move direction
+		# move right
+		write(true, 6)
+
+		# turn on display
+		write(true, 4)
+
+		# set entry mode
+		entry_mode(true, true)
+	end
+
+	fun setup
+	do
+		ds = [d4,d5,d6,d7]
+
+		rs.fsel = new FunctionSelect.outp
+		en.fsel = new FunctionSelect.outp
+		d4.fsel = new FunctionSelect.outp
+		d5.fsel = new FunctionSelect.outp
+		d6.fsel = new FunctionSelect.outp
+		d7.fsel = new FunctionSelect.outp
+
+		rs.write(false)
+		en.write(false)
+
+		write(true, "33".to_hex) # init
+		write(true, "32".to_hex) # init
+		write(true, "28".to_hex) # 2 lines, 5x7
+		write(true, "0C".to_hex) # hide cursor
+		write(true, "06".to_hex) # cursor move right
+		write(true, "04".to_hex) # turn on display
+		write(true, "01".to_hex) # clear display
+	end
+
+	fun write_4_bits(v: Int)
+	do
+		var lb = once [1,2,4,8]
+		for i in [0..4[ do
+			var b = lb[i]
+			var r = b.bin_and(v) != 0
+			var d = ds[i]
+			d.write(r)
+		end
+		pulse_enable
+	end
+
+	fun write_4bits(a,b,c,d:Bool)
+	do
+		d4.write(a)
+		d5.write(b)
+		d6.write(c)
+		d7.write(d)
+		pulse_enable
+	end
+
+	fun pulse_enable
+	do
+		en.write(false)
+		1.bcm2835_delay_micros
+		en.write(true)
+		100.bcm2835_delay_micros
+		en.write(false)
+		1.bcm2835_delay_micros
+	end
+
+	fun write(is_cmd: Bool, cmd: Int)
+	do
+		en.write(false)
+		rs.write(not is_cmd)
+
+		# high byte
+		var hb = once [16,32,64,128]
+		for i in [0..4[ do
+			var b = hb[i]
+			var r = b.bin_and(cmd) != 0
+			var d = ds[i]
+			d.write(r)
+		end
+
+		pulse_enable
+
+		if is_cmd then
+			# wait 5ms
+			5.bcm2835_delay
+		else
+			# wait 200us
+			200.bcm2835_delay_micros
+		end
+
+		# low byte
+		var lb = once [1,2,4,8]
+		for i in [0..4[ do
+			var b = lb[i]
+			var r = b.bin_and(cmd) != 0
+			var d = ds[i]
+			d.write(r)
+		end
+
+		pulse_enable
+
+		if is_cmd then
+			# wait 5ms
+			5.bcm2835_delay
+		else
+			# wait 200us
+			200.bcm2835_delay_micros
+		end
+	end
+
+	fun clear
+	do
+		write(true,1)
+		2.bcm2835_delay
+	end
+
+	fun return_home
+	do
+		write(true,2)
+		2.bcm2835_delay
+	end
+
+	fun text=(v: String)
+	do
+		# do not redraw the samething
+		var last_text = last_text
+		if last_text != null and last_text == v then return
+
+		clear
+		return_home
+		var count = 0
+		for c in v.chars do
+			if c == '\n' then
+				# FIXME, this should work
+				#write(true, "C0".to_hex)
+				# instead we use the following which may not be portable
+
+				for s in [count..40[ do write(false, ' '.ascii)
+				count = 0
+			else
+				write(false, c.ascii)
+				count += 1
+			end
+		end
+
+		self.last_text = v
+	end
+end
+
+# Component for any kind of buttons or switches
+class Switch
+	var pin: RPiPin
+
+	init (pin: RPiPin, pud: PUDControl)
+	do
+		self.pin = pin
+		pin.fsel = new FunctionSelect.inpt
+		pin.pud = pud
+	end
+
+	fun is_down: Bool do return pin.lev
+
+	var last_down: nullable Bool = null
+
+	# Returns true is state (is_down) changed since last call to `changed`
+	fun changed: Bool
+	do
+		var now = is_down
+		var last_down = last_down
+		if last_down == null then
+			self.last_down = now
+			return false
+		else if last_down != now then
+			self.last_down = now
+			return true
+		else return false
+	end
+end
+
+class StepperMotor
+	var pins: Sequence[RPiPin]
+	var delay: Int
+
+	init (delay: Int, a, b, c, d: RPiPin)
+	do
+		pins = [a, b, c, d]
+		self.delay = delay
+
+		for p in pins do p.fsel = new FunctionSelect.outp
+	end
+
+	fun forward(steps: Int)
+	do
+		for s in [0..steps[ do
+			set(true, false, false, false)
+			delay.bcm2835_delay
+			set(true, true, false, false)
+			delay.bcm2835_delay
+			set(false, true, false, false)
+			delay.bcm2835_delay
+			set(false, true, true, false)
+			delay.bcm2835_delay
+			set(false, false, true, false)
+			delay.bcm2835_delay
+			set(false, false, true, true)
+			delay.bcm2835_delay
+			set(false, false, false, true)
+			delay.bcm2835_delay
+			set(true, false, false, true)
+			delay.bcm2835_delay
+		end
+	end
+
+	fun backwards(steps: Int)
+	do
+		for s in [0..steps[ do
+			set(true, false, false, true)
+			delay.bcm2835_delay
+			set(false, false, false, true)
+			delay.bcm2835_delay
+			set(false, false, true, true)
+			delay.bcm2835_delay
+			set(false, false, true, false)
+			delay.bcm2835_delay
+			set(false, true, true, false)
+			delay.bcm2835_delay
+			set(false, true, false, false)
+			delay.bcm2835_delay
+			set(true, true, false, false)
+			delay.bcm2835_delay
+			set(true, false, false, false)
+			delay.bcm2835_delay
+		end
+	end
+
+	fun release do set(false, false, false, false)
+
+	protected fun set(a, b, c, d: Bool)
+	do
+		var bits = new Array[Bool].with_items(a, b, c, d)
+
+		for i in [0..4[ do pins[i].write(bits[i])
+	end
+end
+
+class Buzzer
+	var pin: RPiPin
+
+	fun buzz(delay: Float, times: Int)
+	do
+		assert times > 0
+		assert delay > 0.0
+		var delay_i = (delay*1000.0).to_i
+		for i in [0..times[ do
+			pin.write(true)
+			delay_i.bcm2835_delay_micros
+			pin.write(false)
+			delay_i.bcm2835_delay_micros
+		end
+	end
+end