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Assembly: Problem calling GPLLNK without 32 KB memory expansion


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#26 RXB OFFLINE  

RXB

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Posted Wed Mar 20, 2019 1:57 PM

Not that unusual to use BYTE values as programing vectors from strings or text or data.

 

Miller Graphics did this many times for XML or GPL branches.



#27 HOME AUTOMATION OFFLINE  

HOME AUTOMATION

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Posted Wed Mar 20, 2019 4:52 PM

 

 

The following probably contains a lot of what you already know, but, hopefully, it answers your questions and may help the casual reader with other details:
 
XTABFE contains the address of the 15th vector (16 possible) in the 16th XML vector table (16 possible) referenced by the GPL code: “XML >FE”.  The two-byte, hex code for this is >0FFE.  The XML table:element refrence is >FE, with >Fx referencing the table starting at >8300 and >xE referencing element >1C—hence >831C as the value of XTABFE.
 
GXMLAD contains the address of the GPL XML instruction (>0FFE) we wish the GPL interpreter to execute, which is located at GROM0 address >1675.
 
Regarding the GROM0 addresses >1675 and >176C, GPL instructions are on byte boundaries, not word boundaries as with ALC.  The GPL XML instruction opcode (>0F) appears at both locations.  The XML table:vector byte that follows it in the first reference (>1675) is >FE, which is explained above.  In the Heiner Martin GROM0 dump, the byte following >0F at >176C is >27, which points to the 8th vector (>200E) in the 3rd XML vector table, starting at >2000 in low RAM.  Because the GPL interpreter is byte oriented, it does not matter that the GPL “instructions” at >1675 and >176C are data and never normally executed.  It is sufficient that they happen, fortuitously, to be the actual instructions we need to serve our ends.
 
...lee

 

Lee! This thread was all Greek to me.

I was able to translate your post into my-lingo...

 

 

The beast at Tanagra:
Shaka, when the walls fell,
Temba, his arms open,
Kiazi's children, their faces wet,
Kira at Bashi,
Temba, at rest,
Chenza at court, the court of silence
Kiteo, his eyes closed,
Darmok on the ocean,
Sokath, his eyes open,
Darmok and Jalad on the ocean,
...lee and ralph at El-Adrel.
Lowani under two moons.
...alex of Lowani.

 

 

        -Mirab, with sails unfurled. :waving:

 

 

Spoiler
                         



#28 mizapf OFFLINE  

mizapf

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Posted Wed Mar 20, 2019 4:58 PM

Gilgamesh, a king. Gilgamesh, a king, at Uruk.



#29 Lee Stewart ONLINE  

Lee Stewart

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Posted Wed Mar 20, 2019 5:39 PM

Lee! This thread was all Greek to me.

I was able to translate your post into my-lingo...

 

. . .           

 

Well, then, I guess it was not as arcane as it appeared, initially!  :)

 

...lee



#30 TheBF ONLINE  

TheBF

    Dragonstomper

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Posted Wed Mar 20, 2019 6:50 PM

Lee! This thread was all Greek to me.

I was able to translate your post into my-lingo...

 

 

The beast at Tanagra:
Shaka, when the walls fell,
Temba, his arms open,
Kiazi's children, their faces wet,
Kira at Bashi,
Temba, at rest,
Chenza at court, the court of silence
Kiteo, his eyes closed,
Darmok on the ocean,
Sokath, his eyes open,
Darmok and Jalad on the ocean,
...lee and ralph at El-Adrel.
Lowani under two moons.
...alex of Lowani.

 

 

        -Mirab, with sails unfurled. :waving:

 

 

Spoiler
                         

 

Darmak and Jalad, on the ocean!  :-o



#31 HOME AUTOMATION OFFLINE  

HOME AUTOMATION

    Moonsweeper

  • 428 posts
  • Location:"trapped in interspace"

Posted Wed Mar 20, 2019 10:04 PM

Shaka!
Kadir beneath Mo Moteh?
Temba, his arms open...
Darmok and Jalad at Tanagra,
Temba, at rest. :sleep:

 

                          Mirab, with sails unfurled.






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