ucl 2.0

# Copyright (c) 2005-2008 by Wayne C. Gramlich
# All rights reserved.

# This module uses a PIC16F688:
library $pic16f688

# The system is running at 20MHz:
library clock20mhz
# A microsecond takes 5 cycles at 20MHz:
constant microsecond = 5

# The {$eusart} library defines some baud rate generator constants:
constant $eusart_clock = clock_rate
constant $eusart_factor = 4
library $eusart

# The library of bus access routines for use by a PIC16F688.
library rb2bus_pic16f688

# This module uses 20MHz crystal oscillator; hence mode EC=External Clock:
configure fosc=hs

# All pins on this package are used except RA3.
package pdip
    pin 1 = power_supply
    pin 2 = osc1
    pin 3 = ra4_nc
    pin 4 = ra3_nc, name=nc1
    pin 5 = rx, name=rx, bit=rx_bit
    pin 6 = tx, name=tx, bit=tx_bit
    pin 7 = rc3_nc
    pin 8 = rc2_in, name=in3, mask=in3_mask, bit=in3_bit	# N5
    pin 9 = rc1_in, name=in2, mask=in2_mask, bit=in2_bit	# N4
    pin 10 = rc0_in, name=in1, mask=in1_mask, bit=in1_bit	# N3
    pin 11 = ra2_in, name=in0, mask=in0_mask, bit=in0_bit	# N2
    pin 12 = ra1_nc
    pin 13 = ra0_nc
    pin 14 = ground

origin 0

procedure main
    arguments_none
    returns_nothing

    # This procedure initializes everything and does command decoding.

    local command byte
    local result byte
    local mask byte

    call rb2bus_initialize(19)
    mask := 0xf

    loop_forever
	# Make sure that we have been selected:
	rb2bus_error := $true
	while rb2bus_error
	    call rb2bus_select_wait()
	    command := rb2bus_byte_get()

	switch command >> 6
	  case 0
	    # 00xx xxxx:
	    switch (command >> 3) & 7
	      case 0
		# 0000 0xxx:
		switch command & 7
		  case 0
		    # 0000 0000 (Proximity Get):
		    result := 0
		    if in0
			result@0 := $true
		    if in1
			result@1 := $true
		    if in2
			result@2 := $true
		    if in3
			result@3 := $true
		    result := result & mask
		    call rb2bus_byte_put(result)
		  case 1
		    # 0000 0001 (Mask Set):
		    mask := rb2bus_byte_get()
		  case 2
		    # 0000 0010 (Mask Get):
		    call rb2bus_byte_put(mask)
		  case_maximum 7
	      case_maximum 7
	  case 3
	    # 11xx xxxx:
	    switch (command >> 3) & 7
	      case 7
		# 1111 1xxx:
	        call rb2bus_command(command)


procedure wait
    arguments_none
    returns_nothing

    # This procedure is repeatably called whenever the software
    # is waiting for a byte to arrive from the bus.

    do_nothing


string id = "\16,0,19,1,3,13\IRProximity-4\7\Gramson"