Starting Enhanced BASIC by Lee Davison
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Starting EhBASIC

After reset, if you have set up a Cold/Warm start request, just press C.
E.g.

EhBASIC for 6502 (C) 2001 C/W? C

(The C is not echoed.)

If you have your system start up in at a monitor prompt issue a GO command from the start of the interpreter.
E.g.

> $C000G

EhBASIC will then respond with ..

Memory size ?

Now type either carriage return, in which case EhBASIC calculates available memory space automatically, or enter the desired memory size in either decimal, hex or binary followed by a carriage return.
E.g. to set memory size to 8k.

In decimal ..

Memory size ? 8192

.. or in hex ..

Memory size ? $2000

.. or in binary.

Memory size ? %10000000000000

EhBASICs program memory is then allocated from Ram_base (usually $0300) up to the limit specified. Any remaining RAM, or any RAM not continuous from EhBASICs memory, may be used to contain user subroutines or data.

If you did not enter a number greater than the minimum required to run EhBASIC, or there is not the minimum memory present, then EhBASIC will return to the Memory size ? prompt.

Do not type a number larger than the physical memory present. EhBASIC assumes you know what you are doing and does not check the specified memory size. Trying to use non existent RAM will, at best, corrupt your string variables.
(This check can easily be implemented, the code is already in place but is commented out. See the source for more details.)

There is no Terminal width ? prompt as with some BASICs, the default is for no terminal width limit to be set. However if you wish to set a terminal width, and a TAB step size, there is a WIDTH command available. (See WIDTH in the EhBASIC language reference.)

If the memory sizing was successful then EhBASIC will respond with the total number of bytes available for both programmes and variables and then the Ready prompt.
The display should look something like ..

EhBASIC for 6502 (C) 2001 C/W? Memory size ? 8192 7423 Bytes free Enhanced BASIC Ready _

You are now ready to start using EhBASIC.

To restart EhBASIC After a reset, assuming you have at some time performed a cold start, if you have set up a Cold/Warm start request just press W.
E.g.

EhBASIC for 6502 (C) 2001 C/W? W

(The W is not echoed.)

Or, if you have your system start up in at a monitor prompt, issue a GO command from the warm start point.
E.g.

> $0000G

If all is well, and sometimes if not, EhBASIC will respond with ..

Ready _

After a warn start, if the reset was not caused by a program running amok, the program and all the variables used, will be unchanged. You will not though be able to CONTinue execution.

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