Some retro computer systems include NASCOM BASIC in their ROM firmware.
This is a version of Microsoft BASIC originally written for the NASCOM computer. Typically, this BASIC has had the NASCOM specific hardware features removed and, in some cases, modifications and additions to make it run on the target hardware.
Originally, this BASIC had the ability to SAVE and LOAD programs using the NASCOM’s cassette tape interface. With typical retro computer system’s the SAVE and LOAD features either do not work or have been removed. This leaves only cut and paste as a means of saving and loading BASIC programs.
If you have CP/M then a better version of BASIC is BASIC-80 (or MBASIC). This version of BASIC has SAVE and LOAD functions.
Cut and paste
A BASIC program can be views on a terminal by listing it with the LIST command, as illustrated below.
LIST 10 FOR Z=1 TO 100 20 PRINT Z 30 NEXT Ok
If the “terminal” is actually a terminal emulation program running on a modern computer it is usually possible to capture and save the text sent to the terminal. In this case the required text is:
10 FOR Z=1 TO 100 20 PRINT Z 30 NEXT
To load the program back to the retro computer it is usually possible the “Send” a file from the terminal program or paste it into the terminal program window.
If the retro computer’s serial port has reliable handshaking it should accept the program as if it is being typed in very quickly. If the program gets garbled then it will be necessary to set the terminal program to add delays. This allows the BASIC interpreter time to handle the incoming “typed” program.
The optimum delay times will depend on the system in use but a good starting point is a 1 millisecond delay after each character and a 50 millisecond delay at the end of each line.