[Coco] Strings in DECB

William Astle lost at l-w.ca
Wed Oct 21 12:18:06 EDT 2015


There is no "FRE" function.

On 2015-10-21 10:07, S Klammer wrote:
> If memory serves, a FRE(A$) will also force 'garbage collection'.
>
> Shain
> On Oct 21, 2015 12:19 AM, "Arthur Flexser" <flexser at fiu.edu> wrote:
>
>> 128 or 255 as max length?
>>
>> The relevant ROM code, in the string concatenation routine, is:
>>
>> B61D LDB  ,X       # characters in 1st string
>> B61F LDX <$52    Get 2nd string stack pointer
>> B621 ADDB ,X      Add # characters in 2nd string
>> B623 BHS $B62A  Length okay if no carry
>>    (otherwise ?LS error)
>>
>> As I read this, with my rusty 6809 skills, this indicates a length of 255
>> will be okay for a string, since only a value greater than 255 will set the
>> carry.
>>
>> Art
>>
>>
>> On Tue, Oct 20, 2015 at 10:15 PM, Robert Hermanek <
>> rhermanek at centurytel.net>
>> wrote:
>>
>>> I believe the maximum length is indeed 128.  You may be getting a OS
>> error
>>> because you have not allocated any extra string space... try a CLEAR 1000
>>> statement at the beginning of your test program.
>>>
>>> -RobertH
>>>
>>>
>>> On 10/20/2015 9:01 PM, Theodore (Alex) Evans wrote:
>>>
>>>> I was talking with a friend.  We had a disagreement about the maximum
>>>> length of strings under DECB. He claimed it was 128 and I believe d it
>> was
>>>> 255. So I did some testing. The results were puzzling. I created a
>> string
>>>> and began extending it. Any attempt to extend a string of 100
>> characters or
>>>> more (even with an empty string "") results in an OS error as does any
>>>> attempt to extend a string past 100 characters, but I can define and
>> use a
>>>> string up to 255 characters in length.
>>>>
>>>>
>>>>
>>>>
>>>
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>>>
>>
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>



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