rz.doc

开源串口利用Xmodem,Ymodem,ZModem 下载,上传的程序.在Linux,Arm-Linux 都可使用

	  the command must be given _a_f_t_e_r the file transfer is
	  started(!).  Until terminal server vendors improve the
	  quality of their product, you	may have to get	on their case
	  until	they adequately	support	high performance file
	  transfers.

	  The telnet protcol used by the _t_e_l_n_e_t	program	and terminal
	  servers uses 0xFF (377 octal)	for special control functions.
	  The 0xFF character may cause problems	if it appears in the
	  data stream, especially uploading at high speeds.  With
	  ZCOMM	or Professional-YAM the	0xFF character can be
	  protected by giving the command:
	  set zmtxesc ?

	  Escaping control characters with ZMODEM (sz -e) may help if
	  the transfer gets stuck in the same place on every attempt.
	  Professional-YAM and ZCOMM allow selection of	which control
	  characters need to be	escaped.  In extreme cases 7-bit
	  transmission may be required (see the	Professional-YAM/ZCOMM
	  manual).  If you encounter problems with control characters
	  you should identify which control characters are causing the
	  problem.  Please refer to the	sz -T command in sz.doc	for
	  more help.

	  Flow control between the server and modem is often



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	  defective.  This rarely causes a problem in interactive
	  applications whose short bursts (a screenfull	at most) fit
	  within the available memory buffers.	Streaming protocols
	  such as YMODEM-g, long packet	SuperKermit, and ZMODEM	can
	  overload the available buffering.  Some terminal servers
	  support commands to enable hardware flow control such	as
	  "TERM	FLOWCONTROL HARDWARE IN	OUT"; this assumes the modem
	  attached to the server is properly configured.

	  If the terminal server is too	brain damaged to support flow
	  control, ZMODEM lets you fake	it by setting a	window size.
	  Try
	       sz -w2048 file...
	  to enable software flow control.  Experiment with different
	  window sizes for best	results.

	  Terminal servers are designed	to accept keyboard input from
	  human	operators.  They may lose data when a program sends
	  more data to the host	faster than humans type.  Some servers
	  allow	larger input buffers to	support	file uploads.  If you
	  can upload short files (less than 100	bytes) but not longer
	  files, try
	       sz -w1024 file...
	  with your uploading program.	(Not all programs support this
	  option; use ZCOMM or Professional-YAM.)

	  When both flow control and character transparency are
	  problems, use
	       sz -ew1024 file...
	  as a starting	point.

	  Sometimes the	terminal server	software is defective and must
	  be corrected.	 Please	contact	the network's vendor for
	  corrective procedures.  An alternative is to install direct
	  serial ports for users desiring to upload files.

	  We have also encountered problems when networking software
	  fails	to pass	data after a large amount of data has been
	  sent to the host.  This has happened on a PPP	internet
	  connection which prevented uploads of	large amounts of data
	  via either FTP or a ZMODEM upload (via TELNET).  The PPP
	  connection grinds to a standstill and	not even PING works.
	  The same ZMODEM/TELNET combination easily uploaded ten times
	  as much to a nearby machine connected	by Ethernet.


     PPPPOOOORRRRTTTT WWWWAAAATTTTCCCCHHHHEEEERRRRSSSS
	  Some systems enforce a timeout which disconnects a user
	  after	several	minutes	of keyboard inactivity.	 Long, error
	  free ZMODEM transfers	do not generate	keyboard activity
	  (this	is why ZMODEM is so efficient).	 Restricting the
	  window size with



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	       sz -w16384 file...
	  option generates terminal input at regular intervals even
	  when no error	correction is needed.  If problems persist,
	  try setting a	packet length.
	       sz -l1024 file...
	  (The default ZMODEM packet length is the file	length.)

     NNNNOOOOTTTTEEEESSSS
	  RRRRzzzz,,,, rrrrbbbb,,,, (Reg.)and rrrrxxxx are hard	links to the rz	executable.
	  These	links are automatically	made by	the Makefile.

	  ZMODEM's support of XOFF/XON flow control allows proper
	  operation in many environments that do not support XMODEM
	  uploads.  Unfortunately, not all Unix	versions support input
	  flow control.	 The TTY input buffering on some systems may
	  not adequately buffer	long blocks or streaming input at high
	  speed.  You should suspect this problem when you can't send
	  data to the Unix system at high speeds using ZMODEM,
	  YMODEM-1k or XMODEM-1k, but YMODEM with 128 byte blocks
	  works	properly.

	  The DSZ or Pro-YAM zzzzmmmmooooddddeeeemmmm llll numeric parameter	may be set to
	  a value between 64 and 1024 to limit the burst length
	  ("zmodem pl128").  Although this compromises ZMODEM's
	  throughput, ZMODEM's superior	reliability remains intact.

	  If a program that does not properly implement	the specified
	  file transfer	protocol causes	_r_z to "hang" the port after a
	  failed transfer, either wait for _r_z to time out or keyboard
	  a dozen Ctrl-X characters.  Every reported instance of this
	  problem has been corrected by	using ZCOMM, Pro-YAM, DSZ, or
	  other	program	with a correct implementation of the specified
	  protocol.

	  Many programs	claiming to support YMODEM only	support	XMODEM
	  with 1k blocks, and they often don't get that	quite right.

	  In the case of a few poorly designed microcomputers, sending
	  serial data to a tty port at sustained high speeds has been
	  known	to cause lockups, system halts,	kernel panics, and
	  occasional antisocial	behaviour.  This problem is not	unique
	  to _r_z; newer versions	of Kermit, CRT terminals with screen
	  transmission,	and line noise have the	same effect.  When
	  experimenting	with high speed	input to a system, consider
	  rebooting the	system if the file transfers are not
	  successful, especially if the	personality of the system
	  appears altered.

	  The Unix "ulimit" parameter must be set high enough to
	  permit large file transfers to Unix.

	  Telebit modems must not be set to "spoof" UUCP, XMODEM,



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	  YMODEM, or KERMIT.  Setting one of these spoofing modes
	  interferes with other	protocols.  Telebit's YMODEM spoofing
	  interferes with YMODEM transfers.

	  32 bit CRC code courtesy Gary	S. Brown.  Directory creation
	  code from John Gilmore's PD TAR program.

     NNNNEEEETTTTWWWWOOOORRRRKKKK NNNNOOOOTTTTEEEESSSS
	  Escaping all control characters (sz -e) may help if the
	  transfer gets	stuck in the same place	on every attempt.
	  Professional-YAM and ZCOMM allow selection of	which control
	  characters need to be	escaped.

	  In extreme cases 7-bit transmission may be required (see
	  Professional-YAM/ZCOMM manual).  7-bit transmission requires
	  rz version 4.50 or higher.

	  Please refer to the sz -T command in sz.doc for more help.

     BBBBUUUUGGGGSSSS
	  This version of _r_z does not support some ZMODEM features.
	  Unix flavors of Professional-YAM may be linked to "rz" to
	  support these	features.

	  The ASCII option's CR/LF to NL translation merely deletes
	  CR's;	undos(omen) performs a more intelligent	translation.

     ZZZZMMMMOOOODDDDEEEEMMMM CCCCAAAAPPPPAAAABBBBIIIILLLLIIIITTTTIIIIEEEESSSS
	  _R_z supports ZMODEM command execution (zcommand), incoming
	  ZMODEM binary	(-b), ASCII (-a), escape controls (-e),
	  newer(-n), newer+longer(-N), protect (-p), Crash Recovery(-
	  r), clobber (-y), match+clobber (-Y),	compression(-Z), and
	  append (-+) requests.	 Other options sent by the sender are
	  ignored.  Crash recovery (-r)	cannot be combined with	other
	  options.  The	default	is protect (-p)	and binary (-b).

	  Unix Professional-YAM	provides higher	performance and	other
	  features not supported by _r_z.	Please contact Omen Technology
	  Inc for product information.

	  http://www.omen.com

	  Omen Technology INC
	  Post Office Box 4681
	  Portland OR 97208
	  503-614-0430 (Sales)


     FFFFIIIILLLLEEEESSSS
	  rz.c,	crctab.c, rbsb.c, zm.c,	zmr.c, zmodem.h, rz.1

	  /tmp/rzlog stores debugging output generated with -vv	option



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