Import/Export popdown

The Import/Export popdown (activated with X) enables you to transfer files between the Cambridge Z88 and other makes of computer. It communicates with the other computer through the serial port on the right-hand side of the machine. To use Import/Export you will need an Import/Export program for the other computer, and a connecting lead. Follow the directions supplied with this for a detailed explanation.

Details of the serial port connections are given in Appendix B.

Using Import/Export

The serial parameters should be set up in the Panel before running Import/Export. Also run the communications software on the machine you wish to communicate with.

The program recognises the following commands, which are given by typing the first letter of the command:

 

S)end filePrompts for the name of the file to be transmitted, and then transmits the name and file to the receiving computer. Wildcards are accepted in the file name.
R)eceive file

Prompts for a file name; press  

ENTER
to receive a file and use its transmitted name, or type a name to rename the received file.

B)atch receiveReceives a sequence of named files, terminated by an end batch code.
E)nd batchSends an end batch code (ESC Z).

To send a batch of files use the following procedure:

  1. Give the Batch receive command on the receiving computer
  2. Send each file with a Send file command (or give a '*' wildcard in the file name)
  3. Give an End batch command.

Import/Export protocol

The Import/Export protocol is given here for programmers who want to interface the Cambridge Z88 to a computer by writing their own interface software.

Control sequences

SequenceFunction
ESC NStart of file name
ESC F Start of file/end of file name
ESC E End of file
ESC ZEnd of file or end of list of files
ESC B x xWhere x x is two ASCII digits representing a hex
byte. For example, the byte &A9 is transmitted with
ESC B A 9.
XON = &11Receiver sends to transmitter to restart flow.
XOFF = &13     
Receiver sends to transmitter to stop flow.

Note that all the characters after the ESC code must be in upper-case ASCII.

Transfer protocol

First file, and subsequent files:
ESC N filename ESC F data ESC E

Last file:
ESC N filename ESC F data ESC Z

where data is a sequence of characters in the range &20 to &7E. Codes in the range &00 to &1F and &7F to &FF should be transmitted using the ESC B prefix.

Import/Export will give a Suspended message if a battery low is flagged while sending or receiving, or if the Cambridge Z88 is switched off or the flap is opened. In this case you must repeat the transfer.

The filename can be omitted.

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