class ParPort
# parallel port for Linux-i386
# version 2007.6.1

# ppdev commands
#  2bit; 0:no, 4:write, 8:read
# 14bit; 1:char, 4:int, ...
# 16bit; 70xx:type
PPSETMODE = 0x40047080	#int
PPRSTATUS = 0x80017081	#unsighed char
#PPWSTATUS	OBSOLETE__IOW(PP_IOCTL, 0x82, unsigned char)
PPRCONTROL = 0x80017083	#unsighed char
PPWCONTROL = 0x40017084	#unsighed char
PPRDATA = 0x80017085	#unsighed char
PPWDATA = 0x40017086	#unsighed char
#PPRECONTROL	OBSOLETE__IOR(PP_IOCTL, 0x87, unsigned char)
#PPWECONTROL	OBSOLETE__IOW(PP_IOCTL, 0x88, unsigned char)
#PPRFIFO	OBSOLETE__IOR(PP_IOCTL, 0x89, unsigned char)
#PPWFIFO	OBSOLETE__IOW(PP_IOCTL, 0x8a, unsigned char)
PPCLAIM = 0x0000708b
PPRELEASE = 0x0000708c
PPYIELD = 0x0000708d
#PPFCONTROL = 0x400?708e
PPEXCL = 0x0000708f
PPDATADIR = 0x40047090	#int
PPNEGOT = 0x40047091	#int
PPWCTLONIRQ = 0x40017092	#unsighed char
PPCLRIRQ = 0x80047093	#int
PPSETPHASE = 0x40047094	#int
#PPGETTIME = 0x800?7095
#PPSETTIME = 0x400?7096
PPGETMODES = 0x80047097	#unsigned int
PPGETMODE = 0x80047098	#int
PPGETPHASE = 0x80047099	#int
PPGETFLAGS = 0x8004709a	#int
PPSETFLAGS = 0x4004709b	#int
#PAR=open("/dev/parport0","a+b")

	def initialize()
		@par=open("/dev/parport0","a+b")
		@par.ioctl(PPEXCL)
		@par.ioctl(PPCLAIM)
		@strobe=0	# No.1, output, reverce
		@data=0		# No.2-9, in/out
		@ack=0		# No.10, input, reverse
		@busy=0		# No.11, input, non-reverse
		@pe=0		# No.12, input, non-reverse
		@slct=0		# No.13, input, non-reverse
		@autofxinit=0	# No.14, output, reverse
		@error=0	# No.15, input, reverse
		@init=0		# No.16, output, non-reverse
		@slctin=0	# No.17, output, reverse
		@lock=false
	end

attr_accessor :strobe		# No.1, output, reverse
attr_accessor :data		# No.2-9, in/out
attr_reader :ack		# No.10, input, reverse
attr_reader :busy		# No.11, input, non-reverse
attr_reader :pe			# No.12, input, non-reverse
attr_reader :slct		# No.13, input, non-reverse
attr_accessor :autofxinit	# No.14, output, reverse
attr_reader :error		# No.15, input, reverse
attr_accessor :init		# No.16, output, non-reverse
attr_accessor :slctin		# No.17, output, reverse
#GND	No.18-25
attr_accessor :lock		# to avoid double access

	def close()
		@par.ioctl(PPRELEASE)
		@par.close
	end
	def status()
		d=[0].pack("C")
		@par.ioctl(PPRSTATUS,d)
		d=d.unpack("C")[0]
		d=d/8
		@error=d%2; d/=2
		@slct=d%2; d/=2
		@pe=d%2; d/=2
		@ack=d%2; d/=2
		@busy=d%2; d/=2
	return [@error,@slct,@pe,@ack,@busy]
	end
	def command()
		d=@strobe+@autofxinit*2+@init*4+@slctin*8+0xc0
		@par.ioctl(PPWCONTROL,[d].pack("C"))
	return [@strobe,@autofxinit,@init,@slctin,@inout]
	end
	def command?()
		d=[0].pack("C")
		@par.ioctl(PPRCONTROL,d)
		d=d.unpack("C")[0]
		@strobe=(d & 1); d>>=1
		@autofxinit=d & 1; d>>=1
		@init=d & 1; d>>=1
		@slsctin=d & 1; d>>=1
	return [@strobe,@autofxinit,@init,@slctin]
	end
	def write(d=@data)
		@par.ioctl(PPDATADIR,[0].pack("i"))
		@par.ioctl(PPWDATA,[d].pack("C"))
	end
	def read()
		@par.ioctl(PPDATADIR,[1].pack("i"))
		d=[0].pack("C")
		@par.ioctl(PPRDATA,d)
		d=d.unpack("C")[0]
	return d
	end
end