Cambridge Computer Z88 popdown XY-Modem Version 1.1, 26 December 1999
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Overview 
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A Z88 popdown application for transfering files using the Xmodem and 
Ymodem protocols. Transfer speed around 3300 cps at 38400 bps using 1K 
blocks. Currently supported features are checksum and crc error 
detection, 128 byte and 1K blocksize in any combination, streaming -G 
mode (only for sending). Mailbox function to send a file marked in 
Filer. Batch sending with wildcards. Use :*//* to send all files in all 
directories on all :RAM devices. Ymodem preserves name, size and 
modification date/time of transfered files. User interface similar to 
[]X Imp-Export. 


Installation on EPROM
---------------------
Load XY-Modem.ap0 in top bank at offset 32D4 (hex) on any size eprom 
or other bank if application front dor is changed accordingly. 
Garry Lancaster's RomCombiner could probably be used. 


Installation in RAM
-------------------
See Garry Lancaster's Installer application or BASIC Installer at
http://www.worldofspectrum.org/z88forever/rom-forever.html#installer


Using 
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Press the X key to select Xmodem and the Y key to select Ymodem. 
Press the C key to toggle between Checksum and CRC error checking mode. 
The receiving program controls the type of error checking to be used in 
a transfer. CRC provides better protection against errors in received 
files. Please note that Xmodem -1K often implies use of CRC. 

Press the K key to toggle between 128 byte and 1K blocksizes. 
The sending program controls the blocksize to be used in a transfer. 
1K blocks are faster to transfer. 

The remote receiving program controls if the streaming -G mode should 
be used for sending from XY-Modem. 

An X- or Ymodem program receiving or sending, or trying to, can be 
stopped by sending at least two CAN characters from the remote 
computer. I.e. to stop Z88 XY-Modem, hold the Ctrl key and press X 
several times in the remote terminal window. To stop a remote X- or 
Ymodem program, goto Terminal []V, hold the diamond <> key and press X 
until the transfer is stopped. 

Unsuccessful transfers can be aborted by pressing Esc. 

Note that proper X- and Ymodem programs expect the sending side to be 
started first and then the receiving side. Else you have to wait up to 
ten seconds for the receiver to timeout and retry.

The XY-Modem program is closed by pressing Shift+Enter like in []V 
Terminal. 


What's New 9 April 2002
-----------------------
The binary file XY-Modem-32D4.3F has been renamed to XY-Modem.ap0,
content and functionality is identical, and an XY-Modem.app file has 
been added to ease installation in RAM.


Dennis Groning
www.algonet.se/~dennisgr/z88.htm