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FORTH for the SHARP PC-E500 (S)
10-08-2021, 07:16 PM
Post: #27
RE: FORTH for the SHARP PC-E500 (S)
(10-08-2021 05:36 PM)Klaus Overhage Wrote:  I tried the example on strings at the end of manual.md on two PC-E500s. Both times most of it worked only strlower and strupper not:

There is a typo in the manual. I had tested these examples on my E500, but I remember adding this example later to the manual but then changed it (bad idea), unfortunately causing this issue. There is a missing DUP and a missing SWAP in strlower/strupper. A missing SWAP can unfortunately cause a dictionary overwrite. Here is the corrected version:

Code:
Additional words to convert characters and string buffers to upper and lower case:

    : toupper   ( char -- char ) DUP 'a '{ WITHIN IF $20 - THEN ;
    : tolower   ( char -- char ) DUP 'A '[ WITHIN IF $20 + THEN ;
    : strupper  ( string len -- ) 0 ?DO DUP I + DUP C@ toupper SWAP C! LOOP DROP ;
    : strlower  ( string len -- ) 0 ?DO DUP I + DUP C@ tolower SWAP C! LOOP DROP ;

For example:

    name strupper name TYPE ↲
    JOHN DOE OK[0]

(10-08-2021 05:36 PM)Klaus Overhage Wrote:  Is Forth500 only generated from the assembler source code Forth500.s or are there other Forth source codes that are part of Forth500?

Everything is generated from the single Forth500.s file. This file implements the entire dictionary. Words are defined in machine code or in "compiled" Forth. I don't like such a large monolithic file like this, but the dictionary linkage across all word definitions is essential.

Eventually it would be nice to add Forth source files for extra words, such as for the SEE word to view compiled Forth definitions.

Right now, Forth500 has over 456 built-in words that cover a large portion of the optional standard Forth word sets, not yet counting the 63 words in the float and float-ext word sets to be added soon. All this still fits in about 20KB.

- Rob

"I count on old friends" -- HP 71B,Prime|Ti VOY200,Nspire CXII CAS|Casio fx-CG50...|Sharp PC-G850,E500,2500,1500,14xx,13xx,12xx...
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FORTH for the SHARP PC-E500 (S) - Helix - 09-06-2021, 11:41 PM
RE: FORTH for the SHARP PC-E500 (S) - robve - 10-08-2021 07:16 PM



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