Updated 22 August 2001
C:\Z88> Running in the Dark
C:\Z88> Introduction Using plain old DOS commands on a PC, with a Z88 and a special serial cable, you can transfer files back and forth, print through the PC to a printer and replace the PC screen and keyboard by using the Z88 as a terminal to the PC.
C:\Z88> COPY COM1 FILENAME To receive data to a file on the PC: 1 Enter the above command on the PC. 2a Files in ASCII plain text format like PipeDream, Diary, PrinterEd, Panel and CLI files can always be copied exactly as is by going to Filer []F, mark a file using the arrow and TAB keys, enter the command <>CO and enter :COM as New name. Binary files like BASIC programs can generally not be copied from a PC serial port because the DOS copy command treats some control characters as, you guessed it, control characters. 2b Binary files, and all other files also, can be backed up in a PC file, with embedded Imp-Export protocol information, by going to Imp-Export []X, enter S to send and a filename. To backup the complete RAM of the Z88 into one DOS file, use the wildcard filename :*//* to S)end all files in every RAM device and directory. 2c Z88 spooled printer output can also be copied by pressing []+P, produce some screen output, for example LIST a BASIC program, turn off spooling by pressing []-P. 3 When the file is sent, goto Terminal []V and press <>Z. The DOS End of file marker Ctrl Z will be sent to the PC and the file is saved to disk. C:\Z88> COPY FILENAME COM1 On the Z88, go to Imp-Export []X, press R and Enter to receive to a file, type a filename and press Enter. Now the Z88 will write all received characters to the specified file. Then enter the above command on the PC. When all is sent, normally when the prompt returns, or the line numbers stop increasing on the Z88, press Escape on the Z88 to close the file received to. To transfer a file with embedded Imp-Export protocol information, to the Z88, goto Imp-Export []X, enter R and a filename or just enter to accept the original embedded filename. On the PC enter the above command. When the linenumbers has stopped increasing, press escape on the Z88 and the file is saved. To transfer a DOS-file with embedded Imp-Export protocol information, containing more then one Z88-file to the Z88, use the B)atch receive option in Imp-Export. Binary files like BASIC programs can not be received correctly by Z88 Imp-Export if some character sequence happens to coincide with the Imp-Export protocol. C:\Z88> COPY COM1 LPT1 To use the PC as a parallell Centronics interface for your Z88, enter the above command on the PC. PrintOut <>PO from PipeDream or other application on the Z88 to the PC. When transmission to the PC is finished, (the cursor returns), go to Terminal []V and press diamond Z. Then the printing starts. Copy Help
C:\Z88> CTTY COM1 Redirect standard input and standard output to the serial port so you can use the Z88 Terminal []V as a terminal to the PC. All scrolling output programs, like most DOS commands, could be runned from the Z88. Many Norton Utilities programs has a command line argument to run in command line mode. Graphic programs or programs writing directly to hardware video memory could not be used. C:\Z88> CTTY CON Enter the above command from the Z88 Terminal to return control to the PC keyboard and screen. Ctty Help
C:\Z88> MODE COM1:9600,N,8,1 For file transfers between Z88 and PC, and printing from Z88 through PC to printer, enter the above command on the PC to configure baud rate, parity, number of data bits and stop bits of a serial port for use with the Z88. On the Z88 go to Panel []S, enter Transmit and Receive baudrate 9600, Parity None and Xon/Xoff No. For using the Z88 as a terminal to the PC, use baud rate 1200 or lower in both ends. Mode Help
C:\Z88> DIR | MORE C:\Z88> TYPE FILENAME | MORE Limit screen output to 24 lines at a time to prevent text scrolling off the screen before being read. More Help
C:\Z88> 7MORE The filter program more.com from IBM-DOS 2.10, patched for scrolling only 7 lines at the time and not displaying the -- More -- prompt. Suitable for use with the Z88 screen. Download 7more.com, 384 bytes.
C:\Z88> More Scroll Control Using a baud rate of 1200 or lower allows you time to see what is displayed at the Z88 screen. Baud rates higher then 1200 even makes the Z88 screen miss characters. There is a general way to stop scrolling on the Z88 screen. Press the left shift key and the diamond <> key at the same time. Received characters will then fill up the receive buffer and if you have a working flow control the transmitting PC will be stopped and respond with an 'Abort, Retry Ignore' prompt. Then press A to abort or R to continue.
C:\Z88> EDLIN To edit a file on the PC you need an editor not relying on full screen 25 lines. Edlin is a line editor supplied with DOS from version 1 to 5. Edlin Help Download edlin.com from IBM-DOS 2.10, 4608 bytes. Get the latest version of edlin from the MS-DOS 6.22 Supplemental Utilities.
C:\Z88> Cable Using the PC-Link cable, files can be transfered from the PC to the Z88, but if you try to send a file to the PC the transmission stops after a few lines. DOS by itself does NOT use Xon/Xoff and it does not use hardware flow control when receiving but it does when sending. The Z88 hardware flow control is always active so when trying to send, the Z88 never receives a positive voltage on pin 5 CTS to be able to send. One useful source for a positive voltage is the PC pin 20 DTR instead of the PC-Link connection to pin 4 RTS. The connections would then be exactly the ones recommended in the Z88 User Manual for connecting to a printer, apart from the fact that the printer needs a male connector. A printer cable and a gender changer will do the trick. No flow control is then active when sending to the PC. I only guess it is OK as long as the received data fit in the available RAM and must not be written to disk and interrupting the possibility to correctly receive data. Z88 PC ----- ---------------- 25-pin 9-pin 2 TxD ------> RxD 3 2 3 RxD <------ TxD 2 3 7 GND <-----> GND 7 5 4 RTS ------> CTS 5 8 5 CTS <-+ RTS 4 7 | 8 DCD <-+---- DTR 20 4 9 DTR ----+-> DCD 8 1 | +-> DSR 6 6 Windows NT has useful MODE options for flow control. MODE COMm[:] [BAUD=b] [PARITY=p] [DATA=d] [STOP=s] [to=on|off] [xon=on|off] [odsr=on|off] [octs=on|off] [dtr=on|off|hs] [rts=on|off|hs|tg] [idsr=on|off] Try: MODE COM1 BAUD=9600 PARITY=N DATA=8 STOP=1 XON=OFF OCTS=ON DTR=ON RTS=HS It will probably work with Z88 CTS connected to PC RTS like in the original PC-Link cable outlined below. Let me know.
Z88 PC ----- ---------------- 25-pin 9-pin 2 TxD ------> RxD 3 2 3 RxD <------ TxD 2 3 7 GND <-----> GND 7 5 4 RTS ------> CTS 5 8 5 CTS <------ RTS 4 7 8 DCD <------ DTR 20 4 9 DTR ----+-> DCD 8 1 | +-> DSR 6 6
C:\Z88> Boot Diskette Having a boot diskette with mode.com on it and the last two commands in autoexec.bat reading: MODE COM1:1200,N,8,1 CTTY COM1 was a life saver for me once when my PC monitor broke. Not having the Z88 connected when booting is no problem. After a timeout it just continoues passing the control to the ordinary console with an error message.
C:\Z88> Credits File transfers using the DOS-command COPY and the Z88 []X Imp-Export, was suggested by Ian Sinclair in Z88 Computing, and Aware Technologies in Z88 EPROM and used by Ian Braby in the Z88 Users' Club Software Library.
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