Code Body

To use this file copy and paste this: // #URL-lib "http://pin1.org/forthlib/flb/SD-Card/fat-4.flb" into BV Terminal 3 or here to download.

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *  
// ========== P A R T 4 ======================================
// This section is for write operations. It is much harder to write
// to the card than to read from it as things such as creating 
// directory space, updating the fat, checking free space etc. need 
// to be considered
//
// RTC is needed for creating and modifying files, for devices without
// an RTC then the words will need to be changed  
// This shares many words with fat-1-a, fat-2 and fat-3 so it should
// have the same SID number
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

// REQUIRES: // #URL-Inc "http://pin1.org/forthlib/flb/General/soft1.flb" sid=99 // #URL-lib "http://pin1.org/forthlib/flb/General/pinsel.flb" sid=100 // #URL-lib "http://pin1.org/forthlib/flb/General/SPI.flb" sid=101 // #URL-lib "http://pin1.org/forthlib/flb/SD-Card/MMC.flb" sid=102 // #URL-lib "http://pin1.org/forthlib/flb/General/rtc.flb" sid=103 // #URL-lib "http://pin1.org/forthlib/flb/SD-Card/fat-1.flb" // #URL-lib "http://pin1.org/forthlib/flb/SD-Card/fat-2.flb" // #URL-lib "http://pin1.org/forthlib/flb/SD-Card/fat-3.flb"

Full Contents of File

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
// ========== P A R T 4 ======================================
// This section is for write operations. It is much harder to write
// to the card than to read from it as things such as creating
// directory space, updating the fat, checking free space etc. need
// to be considered
//
// RTC is needed for creating and modifying files, for devices without
// an RTC then the words will need to be changed
// This shares many words with fat-1-a, fat-2 and fat-3 so it should
// have the same SID number
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *

// REQUIRES:
// #URL-Inc "http://pin1.org/forthlib/flb/General/soft1.flb" sid=99
// #URL-lib "http://pin1.org/forthlib/flb/General/pinsel.flb" sid=100
// #URL-lib "http://pin1.org/forthlib/flb/General/SPI.flb" sid=101
// #URL-lib "http://pin1.org/forthlib/flb/SD-Card/MMC.flb" sid=102
// #URL-lib "http://pin1.org/forthlib/flb/General/rtc.flb" sid=103
// #URL-lib "http://pin1.org/forthlib/flb/SD-Card/fat-1.flb"
// #URL-lib "http://pin1.org/forthlib/flb/SD-Card/fat-2.flb"
// #URL-lib "http://pin1.org/forthlib/flb/SD-Card/fat-3.flb"

// ========== FAT - Write ===========================
// write value to cluster, value is a 16 bit word that is
// written in intel format
: fatClust! ( val clust# -- -1|0)
f a t C l u s t // get address and sector of cluster within fat
w o r d 1 6 ! // write new value
d -s e c D s e c ! // store back to card
;

// gets next free cluster in fat, starting at start, use start=0
// to find the first free fat, then use this value to find the next
: fatNF ( start -- clust# [-1 is disk full] )
1 +
T o t a l S e c d @ S e c t C l u s t d @ / // total number of clusters- index
s w a p
d o
i f a t C l u s t @ 0 =
i f i l e a v e t h e n
l o o p
d u p T o t a l S e c d @ > i f d r o p -1 t h e n // disk full check
;

// Serarch for first blank directory entry, directory space goes from
// DIR d @ to RootEntries d @, use e5 as blank or 00
// next free ditrectory entry, addr is within the current sector
// 0 indicates that the directoiry is full
// ** At this stage d# (device) should be set
// sector will be in d-sec
: nfde ( -- en#, -1|0 )
0 // leave marker
R o o t E n t r i e s d @ // number of directory entries
f o r
i d i r -e n t r y // conver en# to address
c @ // get firct char
d u p &e 5 = // look for either e5 or 0
s w a p 0 = // both inducate free
o r i f d r o p i -1 l e a v e t h e n
n e x t
;

// stores update date and time in the dir entry
// to the given entry address
: storeDT ( add -- )
d u p r t c .t i m e m -t i m e !
r t c .d a t e m -d a t e !
;

// stores create date and time in the dir entry
// to the given entry address
: storeDTC ( add -- )
d u p r t c .t i m e c -t i m e !
r t c .d a t e c -d a t e !
;

// writes current directory entry to card, loads in correct sector
// first by using the curent file handle.
// This copies the directory entry in the fiile handle to the
// correct directory entry on the card
: dir! ( -- )
d i r A d d // source address
e n # f @ // get entry number
d i r -e n t r y // get destination address, also gets sector from card
3 2 m o v e // fron file handle to directory
d -s e c D s e c ! // store to card
;

// If a file is erased then all of the clusters except the current
// one needs to be set to 0 and the current cluster is set to &ffff
// If the file is removed form the system then all of the clusters
// including the current clutser need to be erased. This will erase
// ALL of the clusters including the current one
// NOTE THERE IS NO CHECK FOR GOING OVER END OF FAT
: erase-clusters ( start-clust# -- [fat] )
b e g i n
d u p // save previous
f a t C l u s t @ // get next
s w a p 0 s w a p f a t C l u s t ! // write 0 to previous, available
d u p &f f f 8 > // end marker
o v e r 0 = o r // error checking will end if 0 encountered as well
i f 0 s w a p f a t C l u s t ! -1 e l s e 0 t h e n // dont forget last one
u n t i l
;

// when opening an existing file for writing or deleting a file
// the fat clusters need to be reset back to zero to free upthe
// filespace, clust is the starting cluster. All clusters in theFAT
// including this one will be set to 0
// NOTE This erases the contents but not the name of the file
// changes to the directory
: clearFile ( -- )
I s O p e n f @ -1 > i f 1 2 1 e r r o r t h e n // abort if file not open
d i r A d d s t a r t -c l u s t @ d u p // get file starting cluster and make copy
// 12 dir# @ dup // get file starting cluster and make copy
e r a s e -c l u s t e r s // erase ALL clusters in file
&f f f f s w a p f a t C l u s t ! // first clust to &ffff
// directory
0 d i r A d d f i l e S i z e ! // set file size to 0
// 0 13 dir# ! // set file size to 0,
d i r A d d s t o r e D T // update modified dates
D i r ! // update card with modified entry
;

// open existing file for wtiting, this will RESET the file
// in the sence that the contects will be erased
: w-reset ( string handle -- )
r -o p e n e r r o r # 0 =
i f
c l e a r F i l e // clear out clusters
e l s e
." F i l e e r r o r " e r r o r # .
t h e n
;

// deletes REMOVES directory entry, sets first byte to e5,
// frees up file space by setting all clusters to 0
// not this is a pure directory operation, the file is not opened so
// the file handle is not used
: deleteFile ( string -- )
d i r -s e a r c h // search in current device, fills array as wel
i f
>r r @ d i r -e n t r y // get address, save entry #
s t a r t -c l u s t @ d u p // cluster # start for this entry
e r a s e -c l u s t e r s // free up clusters in fat
0 s w a p f a t C l u s t ! // and set current cluster to 0
&e 5 r > d i r -e n t r y c ! // spoil name, dir-entry loads dbuff
d -s e c D s e c ! // store to card
0 e r r o r
e l s e
." f i l e n o t f o u n d " 1 0 3 e r r o r
t h e n
;

// gets the last cluster in a chain, given a starting cluster
// writing
: last-clust ( clust -- last )
b e g i n
d u p f a t C l u s t @ d u p &f f f 7 > i f d r o p -1 e l s e s w a p d r o p 0 t h e n
u n t i l
;

// creates directory entry where sting is in the form fred.txt
// a file does not exist at this present time so the file hanlde
// is not used
: createFile ( string -- )
d u p d i r -s e a r c h i f ." F i l e e x i s t s u s e r e s e t " 1 3 0 e r r o r t h e n
d o t 2 p a d // convert to padded string
d i r $ 1 1 m o v e // save
n f d e // gets next free dir entry
i f
// update fat with ffff in next available cluster
0 f a t N F // get next free fat cluster
&f f f f o v e r f a t C l u s t ! // store to fat - start-clust on stack
// directory operations, en# on stack from nfde
s w a p d i r -e n t r y >r // convert entry to an address, loads Dbuff
r @ s t a r t -c l u s t ! // store to start cluster
d i r $ r @ 1 1 m o v e // name
r @ s t o r e D T C // store DT create
r @ s t o r e D T // store update dat and time
0 r > f i l e S i z e ! // set file size to 0
d -s e c D s e c ! // store to card
e l s e
." c a r d f u l l "
1 3 1 e r r o r // abort
t h e n
;

// given a logical sector it retruns a new file size based
// on the maximum of either the existing size or the new
// calculated size
: newFS ( sect -- new-filesize )
1 + // not sure why I need an extra 1
d i r A d d f i l e s i z e @ // get existing file size
s w a p B y t e s S e c d @ *
m a x // return largest
;

// random write, file must be opened first
// writes contens of fatb to the given LOGICAL sector of that file
// Ls2Phys returns - 1 if the existing cluster is
// exceeded so this is used to create more space.
// This is more complex than it looks, the function is to get next free
// store to current and update current to what was the next free
// Directory size is updated but not stored, this is done in close
: w-random ( handle sect [fatb] -- )
s w a p => f # // make sure correct dir is used
I s O p e n f @ -1 > i f 1 2 2 e r r o r t h e n // abort if file not open
d u p L s 2 P h y s // see if within current range
d u p 0 <
i f
// this is where new file space is created
d r o p // -1
d u p
S e c t C l u s t d @ / // get number of clusters, save size needed ltr
d i r A d d s t a r t -c l u s t @ l a s t -c l u s t s w a p // get last cluster in chain
f o r
d u p f a t N F
d u p r o t f a t C l u s t ! // keep updating empty clusters
n e x t
&f f f f s w a p f a t C l u s t ! // last one
// re-calculate logical sector
d u p n e w F S d i r A d d f i l e s i z e ! // new file size
L s 2 P h y s
s e c ! // save
e l s e
// can write this to existing file space
s e c ! // save it
n e w F S d i r A d d f i l e s i z e ! // new file size using logical sector
t h e n
;

// closes an open file by writing current date and
// file size
: f-close ( file -- )
d u p 0 d e v i c e s b e t w e e n
i f
=> f # // current file handle
I s O p e n f @ -1 > i f 1 2 2 e r r o r t h e n // abort if file not open
d i r A d d s t o r e D T // updata date and time
d i r ! // put back to dir, wrandom updates file size
0 i s O p e n f ! // closed
e l s e
." h a n d l e w r o n g v a l u e " 1 4 5 e r r o r
t h e n
;

// ================= Public interface =========================
: <0>f.create ( string handle -- -1|0 ) // creates and opens file
o v e r c r e a t e F i l e
f .o p e n
;
: <0>f.reset ( string handle -- ) w -r e s e t ; // open and new
: <0>f.del ( string -- ) d e l e t e F i l e ; // deletes file
: <0>f.close ( handle -- ) f -c l o s e ; // closes, updates date + size
: <0>f.wrandom ( handle sector -- ) w -r a n d o m ; // write random
// : <0>f.flush ( handle -- ) => f# f-sec sec! ; // flush any unwritten memory
// Use f.open for appending