[Coco] Color Forth Assistance Request

[Arthur Flexser]

I found a snatch of old code of mine that contains enough information that
I can give you something with more detail.  It doesn't exactly use the
method of the previous message, but instead jumps directly into the
SAVEM command (to $CF7E in Disk Basic 1.1) after storing the appropriate
information to the file name buffer (8 bytes at $94C) and extension buffer
(3 bytes at $954).  It appears that if you then jump to $CF7E with the
registers set as below and pushed onto the stack with a single PSHS
instruction, everything should work:

 Y = start address - 1
 X = end address
 D = exec address
 U = address in your program where you want to resume execution after
the       savem happens

Art



On Sat, Jan 17, 2015 at 2:02 PM, Arthur Flexser <flexser at fiu.edu> wrote:

> One approach to using Basic operations from a machine-language program is
> to set up a buffer containing the command as it would be typed in to Basic,
> possibly already tokenized (i.e., use a "save" token byte instead of Ascii
> SAVE), and then point Basic to this buffer and have it execute the
> command.  There was an article in Rainbow with examples;  maybe someone can
> provide the reference.  Pointing Basic to the buffer essentially involves
> putting its address into $00A6, the location of Basic's parse pointer.
>
> Art
>
> On Sat, Jan 17, 2015 at 12:57 PM, Stephen Pereira <
> spereira1952 at comcast.net> wrote:
>
>> Hello again, all,
>>
>> As you know from my postings about Color Forth, I have been successful
>> with typing in the source code for the Color Forth nucleus (thanks again,
>> Brett, for your assistance finding the last few typos!).  With this, the
>> ORG of the assembly code can be changed to allow Color Forth to be loaded
>> from DECB (HDBDOS in my case) without overwriting any of the disk
>> capabilities.  I also have devised a method to pre-load the code for 1 to 8
>> Forth screens of Forth code that can be subsequently loaded into Color
>> Forth to add in more of the original capability, or the editor, etc.
>>
>> Now, I would like to add in a simple method for loading and saving a set
>> of Forth screens from disk.  What I would like to be able to do is perform
>> LOADM"SCRN1TO8" and SAVEM"SCRN1TO8" &H2380 &H43A0 &H5979 from inside Color
>> Forth.
>>
>> I have taken a look at "Disk Basic Unravelled," and I found memory
>> locations like Disk File Name Buffer (DNAMBF) and Disk File Extension Name
>> Buffer (DEXTBF) which look like places that I could load the file name and
>> extension.  I also found the routine at LC48D which is commented as "Open
>> Disk File For Read or Write."
>>
>> However, I have never written my own code to patch into the DECB system
>> before, so I am skittish, to say the least.
>>
>> What I would like to do is write my own code to load the file name and
>> extension, the starting and ending addresses for the memory block that I
>> would like to save, and call a routine to perform a SAVEM command as if it
>> had come in from the Basic command line.  Similarly, I would like to write
>> the code to load the file name and extension, and call a routine to perform
>> a LOADM command as if it had come in from the Basic command line.
>>
>> Can anyone offer me some advice on where to look to pick up on the
>> specific things that I would have to do in my code to accomplish these
>> operations?
>>
>> Thanks very much, in advance, for your attention and advice.
>>
>> smp
>> --
>> Stephen M. Pereira
>> Bedford, NH  03110
>> KB1SXE
>>
>>
>>
>> --
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>> Coco at maltedmedia.com
>> https://pairlist5.pair.net/mailman/listinfo/coco
>>
>
>