Demo/sgi/video/VCR.py

import fcntl
import IOCTL
from IOCTL import *
import sys
import struct
import select

DEVICE='/dev/ttyd2'

def packttyargs(*args):
	if type(args) <> type(()):
		raise 'Incorrect argtype for packttyargs'
	if type(args[0]) == type(1):
		iflag, oflag, cflag, lflag, line, chars = args
	elif type(args[0]) == type(()):
		if len(args) <> 1:
			raise 'Only 1 argument expected'
		iflag, oflag, cflag, lflag, line, chars = args[0]
	elif type(args[0]) == type([]):
		if len(args) <> 1:
			raise 'Only 1 argument expected'
		[iflag, oflag, cflag, lflag, line, chars] = args[0]
	str = struct.pack('hhhhb', iflag, oflag, cflag, lflag, line)
	for c in chars:
		str = str + c
	return str

def nullttyargs():
	chars = ['\0']*IOCTL.NCCS
	return packttyargs(0, 0, 0, 0, 0, chars)

def unpackttyargs(str):
	args = str[:-IOCTL.NCCS]
	rawchars = str[-IOCTL.NCCS:]
	chars = []
	for c in rawchars:
		chars.append(c)
	iflag, oflag, cflag, lflag, line = struct.unpack('hhhhb', args)
	return (iflag, oflag, cflag, lflag, line, chars)

def initline(name):
	fp = open(name, 'r')
	ofp = open(name, 'w')
	fd = fp.fileno()
	rv = fcntl.ioctl(fd, IOCTL.TCGETA, nullttyargs())
	iflag, oflag, cflag, lflag, line, chars = unpackttyargs(rv)
	iflag = iflag & ~(INPCK|ISTRIP|INLCR|IUCLC|IXON|IXOFF)
	oflag = oflag & ~OPOST
	cflag = B9600|CS8|CREAD|CLOCAL
	lflag = lflag & ~(ISIG|ICANON|ECHO|TOSTOP)
	chars[VMIN] = chr(1)
	chars[VTIME] = chr(0)
	arg = packttyargs(iflag, oflag, cflag, lflag, line, chars)
	dummy = fcntl.ioctl(fd, IOCTL.TCSETA, arg)
	return fp, ofp

#ifp, ofp = initline('/dev/ttyd2')
#while 1:
#	print 'GO'
#	inset, d, d = select.select([sys.stdin, ifp], [], [])
#	if sys.stdin in inset:
#		cmd = eval(sys.stdin.readline(100))
#		print 'CMD:', `cmd`
#		if cmd:
#			ofp.write(cmd)
#			ofp.flush()
#	if ifp in inset:
#		data = ifp.read(1)
#		print 'LEN', len(data), 'DATA', `data`

error = 'VCR.error'

# Commands/replies:
COMPLETION = '\x01'
ACK  ='\x0a'
NAK  ='\x0b'

NUMBER_N = 0x30
ENTER  = '\x40'

EXP_7= '\xde'
EXP_8= '\xdf'

CL   ='\x56'
CTRL_ENABLE = EXP_8 + '\xc6'
SEARCH_DATA = EXP_8 + '\x93'
ADDR_SENSE = '\x60'

PLAY ='\x3a'
STOP ='\x3f'
EJECT='\x2a'
FF   ='\xab'
REW  ='\xac'
STILL='\x4f'
STEP_FWD ='\xad'
FM_SELECT=EXP_8 + '\xc8'
FM_STILL=EXP_8 + '\xcd'
DM_OFF=EXP_8 + '\xc9'
DM_SET=EXP_8 + '\xc4'
FWD_SHUTTLE='\xb5'
REV_SHUTTLE='\xb6'

class VCR:
	def init(self):
		self.ifp, self.ofp = initline(DEVICE)
		return self

	def _cmd(self, cmd):
##		print '>>>',`cmd`
		self.ofp.write(cmd)
		self.ofp.flush()

	def _waitdata(self, len, tout):
		rep = ''
		while len > 0:
			ready, d1, d2 = select.select([self.ifp], [], [], tout)
			if ready == []:
##				if rep:
##					print 'FLUSHED:', `rep`
				return None
			data = self.ifp.read(1)
##			print '<<<',`data`
			if data == NAK:
				return NAK
			rep = rep + data
			len = len - 1
		return rep

	def _reply(self, len):
		data = self._waitdata(len, 10)
		if data == None:
			raise error, 'Lost contact with VCR'
		return data

	def _getnumber(self, len):
		data = self._reply(len)
		number = 0
		for c in data:
			digit = ord(c) - NUMBER_N
			if digit < 0 or digit > 9:
				raise error, 'Non-digit in number'+`c`
			number = number*10 + digit
		return number

	def _iflush(self):
		dummy = self._waitdata(10000, 1)
##		if dummy:
##			print 'IFLUSH:', dummy

	def simplecmd(self,cmd):
		for ch in cmd:
			self._cmd(ch)
			rep = self._reply(1)
			if rep == NAK:
				return 0
			elif rep <> ACK:
				raise error, 'Unexpected reply:' + `rep`
		return 1

	def _number(self, number, digits):
		if number < 0:
			raise error, 'Unexpected negative number:'+ `number`
		maxnum = pow(10, digits)
		if number > maxnum:
			raise error, 'Number too big'
		while maxnum > 1:
			number = number % maxnum
			maxnum = maxnum / 10
			digit = number / maxnum
			ok = self.simplecmd(chr(NUMBER_N + digit))
			if not ok:
				raise error, 'Error while transmitting number'

	def wait(self):
		self._iflush()
		while 1:
##			print 'SENDCL'
			self._cmd(CL)
			rep = self._waitdata(1, 2)
##			print `rep`
			if rep in ( None, CL, NAK ):
				continue
			break
		if rep <> ACK:
			raise error, 'Unexpected reply:' + `rep`
		dummy = self.simplecmd(CTRL_ENABLE)

	def waitready(self):
		rep = self._waitdata(1, 60)
		if rep == None:
			raise error, 'Command not finished in one minute'
		if rep not in  (COMPLETION, ACK):
			self._iflush()
			raise error, 'Unexpected waitready reply:' + `rep`

	def play(self): return self.simplecmd(PLAY)
	def stop(self): return self.simplecmd(STOP)
	def ff(self):   return self.simplecmd(FF)
	def rew(self):  return self.simplecmd(REW)
	def eject(self):return self.simplecmd(EJECT)
	def still(self):return self.simplecmd(STILL)
	def step(self): return self.simplecmd(STEP_FWD)

	def goto(self, (h, m, s, f)):
		if not self.simplecmd(SEARCH_DATA):
			return 0
		self._number(h, 2)
		self._number(m, 2)
		self._number(s, 2)
		self._number(f, 2)
		if not self.simplecmd(ENTER):
			return 0
		self.waitready()
		return 1

	# XXXX TC_SENSE doesn't seem to work
	def faulty_where(self):
		self._cmd(TC_SENSE)
		h = self._getnumber(2)
		m = self._getnumber(2)
		s = self._getnumber(2)
		f = self._getnumber(2)
		return (h, m, s, f)

	def where(self):
		return self.addr2tc(self.sense())

	def sense(self):
		self._cmd(ADDR_SENSE)
		num = self._getnumber(5)
		return num

	def addr2tc(self, num):
		f = num % 25
		num = num / 25
		s = num % 60
		num = num / 60
		m = num % 60
		h = num / 60
		return (h, m, s, f)

	def tc2addr(self, (h, m, s, f)):
		return ((h*60 + m)*60 + s)*25 + f

	def fmmode(self, mode):
		if mode == 'off':
			arg = 0
		elif mode == 'buffer':
			arg = 1
		elif mode == 'dnr':
			arg = 2
		else:
			raise error, 'fmmode arg should be off, buffer or dnr'
		if not self.simplecmd(FM_SELECT):
			return 0
		self._number(arg, 1)
		if not self.simplecmd(ENTER):
			return 0
		return 1

	def fmstill(self):
		if not self.simplecmd(FM_STILL):
			return 0
		self.waitready()
		return 1

	def dmcontrol(self, mode):
		if mode == 'off':
			return self.simplecmd(DM_OFF)
		if mode == 'multi freeze':
			num = 1000
		elif mode == 'zoom freeze':
			num = 2000
		elif mode == 'digital slow':
			num = 3000
		elif mode == 'freeze':
			num = 4011
		else:
			raise error, 'unknown dmcontrol argument: ' + `mode`
		if not self.simplecmd(DM_SET):
			return 0
		self._number(num, 4)
		if not self.simplecmd(ENTER):
			return 0
		return 1

	def fwdshuttle(self, num):
		if not self.simplecmd(FWD_SHUTTLE):
			return 0
		self._number(num, 1)
		return 1

	def revshuttle(self, num):
		if not self.simplecmd(REV_SHUTTLE):
			return 0
		self._number(num, 1)
		return 1