# TRANS - Transmit a line of the file to the remote. Cadnet V. 3.0.
#
# Calling Sequence:
#	call trans (line, linlen, ids)
#
# Where:
#	line   - the line of data to be transmitted
#	linlen - length of line
#	ids    - status code
#
# Note:
#	In the following notes, the string transmitted to the remote is listed
#	first, followed by the response string sent by the remote back to XMT.
#
#	The format of a data line representing a logical record of length 0 is:
#		<LF> <NULL> <CR>
#		<LF> <transmission length> [logical record length] <CR>
#
#	The format of a data line not holding the end of the logical record is:
#		<LF> [data subsequences] <SO> <CR>
#		<LF> <transmission length> <CR>
#
#	The format of a data line holding the end of the logical record is:
#		<LF> [data subsequences] <CR>
#		<LF> <transmission length> [logical record length] <CR>
#

	subroutine trans (line, linlen, ids)

	byte		line (transmissionlength)
	integer*2	linlen, ids

	byte		sndlin (1024), respon (responselength)
	integer*2	icount, ihigh, low, lnsize, trsize

# Encode and send the record to the remote.
if (linlen == 0)
	{	# zero length logical record
	# Send data line to remote
	write (rem, 100) null

	# Wait for and decode response string from remote.
	call readln (respon, icount)
	trsize = 2 + oct100
	ihigh = respon (3)
	low = respon (4)
	lnsize = (ihigh - oct100) * oct100 + (low - oct100)
	if ((icount != 4) \ (respon(2) != trsize) \ (linlen != lnsize))
		{	# Illegal response from remote.
		ids = -1
		write (err, 101)
		return
		}
	return
	}
else
	{	# non-zero length logical record
	# Translate the logical record into the appropriate subsequences
	j = 1 			# j next position in sndlin (transmit line)
	do i = 1, linlen
		{
		if ((line (i) >= null) & (line (i) < space))
			{	# Control character
				# Send '<ENQ> <char + oct100>'
			sndline (j) = enq
			sndline (j + 1) = line (i) + oct100
			j = j + 2
			}
		else if ((line (i) >= space) & (line (i) < oct200))
			{	# Printing character
				# Send '<char>'
			sndlin (j) = line (i)
			j = j + 1
			}
		else if ((line (i) >= oct200) & (line (i) < oct237))
			{	# Negative character (lower values)
				# Send '<BS> <line & oct177 \ oct100>'
			sndlin (j) = bs
			sndlin (j + 1) = (line (i) & oct177) \ oct100
			j = j + 2
			}
		else if ((line (i) >= oct237) & (line (i) < oct400))
			{	# Negative character (higher values)
				# Send '<BEL> <line & oct177>'
			sndlin (j) = bel
			sndlin (j + 1) = line (i) & oct177
			j = j + 2
			}
		else
			{	# Logic error: unrecognized character
			write (error, 103) line (i)
			call exst (4)
			}
		}

	# Write logical record as a set of data lines of length linsiz.
	i = 1
	while (j - i > linsiz)
		{	# Data line doesn't contain end of logical record
		# Send data line to remote
		write (rem, 100) (sndlin (ii), ii=i,i+linsiz-1), so
		i = i + linsiz

		# Wait for and decode response string from remote.
		call readln (respon, icount)
		if ((icount != 2) \ (respon (2) != linsiz + 1 + oct100))
			{	# Illegal response from remote.
			ids = - 1
			write (err, 101)
			return
			}
		}

	# Write rest of logical record as a data line of length < linsiz
		# Send data line to remote
		write (rem, 100) (sndlin (ii), ii=i,j-1)

		# Wait for and decode response string from remote.
		call readln (respon, icount)
		trsize = j - i + oct100
		ihigh = respon (3)
		low = respon (4)
		lnsize = (ihigh - oct100) * oct100 + (low - oct100)
		if ((icount != 4) \ (respon(2) != trsize) \ (linlen != lnsize))
			{	# Illegal response from remote.
			ids = -1
			write (err, 101)
			return
			}
		return
	}

100	format (x, 251a1)
101	format (' remote not receiving properly, aborting communiction')
103	format (' Unrecognized character in subroutine TRANS:', i5)
	end