Re: CF05, Block 20 (USB), =?windows-1255?Q?=93free=94?=

Hi Nick,

First, sorry, that hyperlink in my email wasnג€™t supposed to be there 
(Thunderbird being too clever).  Thanks for the listing.

I think it might not be a specific USB pointג€”itג€™s the command ג€okג€ below 
(listing still right at bottom). 

ok show black screen white regs keyboard ; free 67106904
3fff800 free !

free is magenta
6706904 is green
3fff800 dark yellow
free yellow
! yellow

That 3fff800 is a bit smaller than 4000000, which is 64MB.  But why that 
number?  Is there a simple explanation of colorForthג€™s memory map anywhere?

There is the following in Josh Grams source (the one I use):
;   100000 dictionary
;    a0000 return stack (main)
;    9f400 data stack
;    9dc00 return stack (draw)
;    9d000 data stack
;    9b800 return stack (serve)
;    9ac00 data stack
;    99400 divider (bottom of rstack, top of floppy buffer)
;    94c00 floppy buffer
;    92c00 forth dictionary addrs (room for 2048 entries)
;    90c00 forth dictionary names
;     7c00 BIOS loads boot sector here; we immediately move it to 0
;     4800 source
;     3000 icons
;        0 the colorforth kernel

So this goes up to 100000h (1MB)

I might be barking up entirely the wrong tree though.  Maybe it is a 
peculiar USBג€“affected memory address.

Thanks,
Jason

Nick Maroudas said the following on 11/10/2008 07:04:
> Quoting Jason Kemp <[email protected]>:
>
>   
>> ... " Hi,
>> ... " 
>> ... " There is a variable, free, whose comment says
>> ... " ג€current address in work 
>> ... " spaceג€ in this block.  The initial value is
>> ... " 3fff800 
>> ... " <http://slug/colorforth/index.php?page=3fff800>
>> ... " 
>> ... " Where does this address come from?
>> ... " 
>> ... " Sorry, I can't point to an html listing of the
>> ... " code on the Web
>> ... " 
>> ... " Thanks,
>> ... " Jason
>> ... " 
>>     
>
> Nick here:  I can't help re USB, but here is an html
> listing of CF05 in text form (original URL owner please
> claim)
>
>
> --------------------------------------------------------------------------------
> {block 20} 
> usb macro macro searched first
> p@ a! dup ed 1, ; cyan macro compilation
> bswap c80f 2, ;
> b! ?lit 589 2, , drop ; forth
> ad n-n 2* ff80 e800 8000e820 pci -1 + or ;
> u@ n-n ad p@ ;
> regs 12 for i u@ 4 h.n space i ad 4 h.n cr -next ;
> ok show black screen white regs keyboard ; free 67106904
> 3fff800 free !
> toggle 7 ;
> array pop + ; magenta variables
> string align array 42535500 , 143 , 20000 , a008000 , 28
> , 0 , 1 , 0 ,
> +fr a-a 1 +
> fr n-a dup 3ff and drop if ; then fffffc00 + ;
> frame 4 u@ 2/ 2/ 1 + fr ;
> td, free @ ffffff7f and free ! 22 load
> move sd 128 for over @ over ! 1 dup v+ next drop drop ;
> yellow variable in green is literal
> rest 31 block 1055 486 -31 + read ;
> cf 0 1024 nc @ 18 * write ;
> gds 4096 swap 255 + 256 / write ;
> bot 3000 block dup 0 16 read 2000 block over move 2000
> block over 128 6 * + move 0 16 write ; 
>
> --------------------------------------------------------------------------------
> {block 21} 
> p@ read register
> p! write register
> bswap byte-swap eax
> b! store eax into literal byte address
> ad byte-address of usb 16-bit register
> u@ read usb register
> regs display usb registers
> ok start register display
> free current address in work space
> frames initialize 1024 frame pointers to off
> +fr increment frame address - wrap
> frame address of first accessible frame
> td, wrap free 1st word of transfer
> t, compile word into work space
> b read 1024-byte blocks offset by 2000 
>
> --------------------------------------------------------------------------------
>
>