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About the ShrinkIt archive: A2.P8.FBS.SHK
Uploaded by Charles T. 'Dr. Tom' Turley 
11/28/98

First and most important: Format your RAM5 disk on your Apple IIe (enhanced) or IIgs in HFS format(or a standard 800k 3.5 disk) in HFS format and make sure the RAM disk is 800k in size.  You'll need to do this because of the archive contents tota file sizes and also because - when you unshrink the archive with Shrinkit  - some of the files have file names that need to remain as they are named and they are too long for ProDOS to handle.

The article below is included in the archive and is presented in this INFO
text file to give you a general concept of what this archive is all about and
what you (concluding you are a programmer) can do with the contents of it.

If you've ever wished to add support in a ProDOS 8 program for digitizing
with any Apple IIe (enhanced) or IIgs model that runs ProDOS 8, allowing the user to do a nice, clean color or greyscale graphic scan and save it as; hi-res, double hi-res or even super-hires (with the IIgs), using most any of the current and fairly low priced SCSI flatbed scanners available today, this archive will give you that ability.

Cheers & Enjoy,
Tom

-------------------
SCANNING FROM PRODOS

MATT GULICK

This article shows just how easy it is to include support for scanner 
hardware in your application program. With just a little effort, you can 
add significant functionality to your program. 

In this article, we explore using the Apple Scanner (a flatbed scanner) 
and the Apple II High-Speed SCSI Card with either an Enhanced Apple IIe 
computer or an Apple IIGS computer running the ProDOS-8 operating 
system. (A future article will cover GS/OS.) The concepts presented here 
can be used for any scanner that can be connected to an Apple IIe or 
Apple IIGS via the Apple II SCSI card. 

For this article, we limit our discussion to the graphics modes 
available on the Apple IIe (HiRes and Double HiRes modes). These modes 
are more limited in resolution and color generation than the Super HiRes 
mode available on the IIGS, but they allow our sample program to run on 
most of the current Apple II family of systems in use today. We focus on 
1-bit-per-pixel halftone and line art images. In so doing, we are able 
to display the data on the screen easily. 
PLAYING HIDE-AND-SEEK WITH THE SCANNER

...98, 99, 100. Ready or not, here we come. Under the ProDOS-8 operating 
system, we don't have access to the loaded drivers that have been 
written for the GS/OS environment. Since the scanner is a character 
device, data is returned in bytes rather than in blocks. ProDOS-8 can't 
help us read from character devices, so we need to walk the slots 
looking for the card we want and then talk to the card directly to find 
the device we want. 

APPLE HIGH-SPEED SCSI CARD, WHERE ARE YOU?
We must first find which slot the high-speed SCSI card is in. We start 
at slot 7 and work our way down. In the following code segment, we look 
for a SmartPort device in the current slot. If one is found, we must 
determine if it is a SCSI card that supports extended SmartPort calls. 
Finally, we need to make sure that this is the type of card we want. In 
other words, "Is this card from a vendor whose command set I 
understand?" See Code Sample 1. 

;*******************************************************
;
;   CODE SAMPLE 1
;
;   In this first code segment, we walk the slots starting 
;   at slot 7, looking first for a card of any kind. Once
;   found, we check the ID bytes for a SmartPort card.
;   Once found, we check the ID Type byte to see if it is
;   a SCSI card. If the card passes all these tests, we 
;   then issue a Device $00 Status $00 call to further 
;   ensure that this is the Apple II High-Speed SCSI Card.
;
;*******************************************************

find_card
                        ;
                        ; Save the current Zero
                        ; Page values before
                        ; using them.
                        ;
        lda <My_ZPage
        pha
        lda <My_ZPage+1
        pha
                        ;
                        ; Start at slot 7.
                        ;
        lda #slot_7
        sta <My_ZPage+1      ;Zero Page
        sta slot+1      ;For Safe keeping
        stz <My_ZPage
        stz slot
                        ;
                        ; Is it a SmartPort card?
                        ;
@chk_smart  ldy #Blk_sigl
        lda (My_ZPage),y    ;Block_device Signature Byte
        cmp #$20            ;#1 = $20
        bne @next_slot

        ldy #Blk_sig2
        lda (My_ZPage),y    ;Block_device Signature Byte
        bne @next_slot      ;#2 = $00

        ldy #Blk_sig3
        lda (My_ZPage),y    ;Block_device Signature Byte
        cmp #$03            ;#3 = $03
        bne @next_slot

        ldy #SPort_sig
        lda (My_ZPage),y    ;SmartPort Signature Byte
        bne @next_slot      ;#1 = $00
                        ;
                        ; We have a SmartPort
                        ; device. Is it SCSI with
                        ; Extended SmartPort?
                        ;
        ldy #SPort_ID
        lda (My_ZPage),y
        and #Ext_SPort+\
            SCSI
        cmp #Ext_SPort+\
            SCSI
        bne @next_slot
                        ;
                        ; Is it an Apple II 
                        ; High-Speed SCSI Card?
                        ;
        jsr is_it_appl
        bcc @exit
                        ;
                        ; Check the next slot.
                        ;
@next_slot  lda <My_ZPage+1
        dec a
        sta <My_ZPage+1
        sta slot+1
        cmp #slot_1
        bge @chk_smart
        lda #No_dev     ;No Device Error
                        ;
                        ; Clean exit
                        ;

@exit       tax
        pla
        sta <My_ZPage+1
        pla
        sta <My_ZPage
        txa

        cmp #$01        ;Set Carry if Non-Zero.
        rts
                        ;
                        ; This routine determines
                        ; if the card is the new
                        ; high-speed SCSI card.
                        ;
is_it_appl  ldy #$ff
        lda (My_ZPage),y
        clc
        adc #$03        ;Set SmartPort Entry Address.
        sta card_ntry

        lda <My_ZPage+1
        sta card_ntry+1

        jsr call_card
        dc.b    $00     ;Status Call Command Number
        dc.w    stat_list1
                        ;
                        ; Check the results.
                        ;
        lda stat_data+2     ;Low Byte of Vendor ID
        cmp #$01            ;Must be $01
        bne @non_apple

        lda stat_data+3     ;High Byte of Vendor ID
        bne @non_apple      ;Must be $00

        lda stat_data+4     ;Low Byte of Version
        bne @non_apple      ;Should be Null

        lda stat_data+5     ;High Byte of Version
        bne @non_apple      ;Should be Null


        clc             ;Acc. 0 by previous LDA
        bra @done
@non_apple  lda #No_dev     ;Device not found

        sec
                        ;
                        ; Restore ZPage.
                        ;
@done   pha
        php
        lda slot
        sta <My_ZPage
        lda slot+1
        sta <My_ZPage+1
        plp
        pla
        rts

slot        dc.w    $0000

;*******************************************************

call_card   jmp (card_ntry)

card_ntry   dc.w    $0000

;*******************************************************

stat_list1  dc.b    $03         ;PCount = 3
        dc.b    $00         ;Device = Card
        dc.w    stat_data       ;Data returned here
        dc.b    $00         ;Get Host Status Call

;*******************************************************

stat_data   dcb.b 64,0          ;Our Buffer

;*******************************************************


FINDING THE SCANNER IN A HAYSTACK
Now that we've found the card, or at least a card (there may be more 
than one), we need to ask the card, politely of course, if it has seen 
the scanner and if so, where. See Code Sample 2. 

"Excuse me SCSI card, we're taking a census and would like to ask you a 
few questions if you don't mind. How many devices live at this slot? I 
see, and are any of them by chance character devices? Hmmm, too bad. 
I'll try the next slot. Sorry to bother you, and thank you for your 
time." 

. . . a few slots later . . ."Hi, we're taking a poll and would like 
your response to a few short questions. How many devices live at this 
slot? That many, great. Are any of them character devices? Getting 
warmer. May we come in to talk to them? Thank you." 

;*******************************************************
;
;   CODE SAMPLE 2
;
;   In this code segment, we walk the unit numbers from the
;   SCSI card starting at unit 2 and going to unit 0 to
;   get the actual unit number count. Once this is
;   done, we start at unit 1 and walk forward until we
;   find the scanner.
;
;*******************************************************

    find_scanr
                        ;
                        ; First we issue a
                        ; Status call to device
                        ; number 2. This call
                        ; forces the card to
                        ; build its tables if it
                        ; has not yet done so.
                        ;
        lda #$02
        sta dev_num2
        stz stat_code2

        jsr call_card
        dc.b    $00         ;Status Call Command Number
        dc.w    stat_list2
        bcs @error
                        ;
                        ; Now call unit 0 to
                        ; find out the total
                        ; device count.
                        ;
        stz dev_num2
        jsr call_card
        dc.b    $00         ;Status Call Command Number
        dc.w    stat_list2
        bcs @error

        lda stat_data2      ;Get the Total Device
        sta dev_count       ;Count.

        lda #$03            ;Set up for DIB Status
        sta stat_code2      ;calls.

@loop   lda dev_num2        ;First time we increment
        cmp dev_count       ;a zero giving a device
        bge @error          ;number of 1.

        inc dev_num2
        jsr call_card
        dc.b    $00         ;Status Call Command Number
        dc.w    stat_list2
        bcs @error

        lda d_type
        cmp #$08            ;Is it Type = Scanner?
        bne @loop           ;No

        lda d_stype
        cmp #$A0            ;Subtype = $A0?
        bne @loop           ;No
                        ;
                        ; Scan string is a Pascal
                        ; string (a length byte
                        ; followed by ASCII). We
                        ; want to make sure that 
                        ; both the length and the 
                        ; text in 'scan_str' match
                        ; the data returned in
                        ; 'id_str_len' and 'id_str'.
                        ;
        ldx id_str_len
@str_loop   lda id_str_len,x
        cmp scan_str,x
        bne @loop
        dex
        bne @str_loop

        lda dev_num2    ;We have our scanner.
        sta scan_dnum
        lda #No_Err
        clc
        rts

@error  lda #No_dev     ;Device not found.
        sec
        rts

;*******************************************************

scan_str    dc.b    'APPLE    SCANNER ';4 Spaces between
                         ;1 Space after
dev_count   dc.b    $00

;*******************************************************

scan_dnum   dc.b    $00         ;Scanner Device Number

;*******************************************************

stat_list2  dc.b    $03         ;PCount = 3
dev_num2    dc.b    $00         ;Device number
        dc.w    stat_data       ;Data returned here
stat_code2  dc.b    $00         ;Status Code

;*******************************************************

stat_data2                  ;Our Buffer. Used over.
d_stat  dc.b    $00         ;Device Status Byte
blk_low dc.b    $00         ;Block Count (Low)
blk_mid dc.b    $00         ;Block Count (Mid)
blk_hi  dc.b    $00         ;Block Count (High)
id_str_len  dc.b    $00         ;ID String Length
id_str  dcb.b 16,$00        ;ID String (16 Bytes)
d_type  dc.b    $00         ;Device Type
d_stype dc.b    $00         ;Device Subtype
d_version   dc.w    $00         ;Version Word

;*******************************************************

SCANNING FOR 'STILL LIFE' FORMS, CAPTAIN

Now that we've found the scanner, we're ready to plant our thoughts in 
it. We do this by sending a few commands to the scanner, telling it what 
type of image we expect and what the scanner should do with the image 
before transferring it to us. 

WE ARE ONE--OUR THOUGHTS ARE YOUR THOUGHTS
First, we send the scanner the halftone filter we want to use; then we 
set our scan window. 

Halftone filter. Since we're going to do a halftone scan in our example, 
we issue a call to set the halftone filter. Note that we don't need to 
set this halftone filter if we choose to use one of the default filters 
or if we are going to scan in Line Art mode. A halftone filter is 
nothing more than a defined threshold for each pixel of a 4 by 4 block. 
As the image under the mask changes intensity, the filter causes more or 
fewer of the dots to be black; the rest of the dots are white. The 4 by 
4 block then becomes darker or lighter depending on the number of dots 
that are set to white within it, simulating gray tones even though our 
graphic mode knows only black and white. 

Setting the halftone filter is easy; picking the filter pattern that 
best suits your needs is harder. Use one of the built-in patterns unless 
you have a better one. We use a simple Bayer type filter for this 
example. See Figure 1 and Code Sample 3. 



Figure 1 Simple Bayer Pattern 


;*******************************************************
;
;   CODE SAMPLE 3
;
;   In this code segment, we issue an Apple Scanner SEND
;   command by using the Apple SCSI Card Generic SCSI
;   call ($2B). By so doing, we can send our halftone
;   filter to the scanner.
;
;*******************************************************
htone_filter
                        ;
                        ; Issue the call.
                        ;
        lda scan_dnum
        sta dev_num3

        jsr call_card
        dc.b    $04         ;Control Call Command Number
        dc.w    cmd_list3
        rts

;*******************************************************

cmd_list3   dc.b    $03         ;PCount = 3
dev_num3    dc.b    $04         ;Device number
        dc.w    filter_data     ;Pointer to data
        dc.b    $2B         ;Control Code

;*******************************************************

filter_data                 ;Our Data
        dc.w    24          ;Total Length of Parms
        dc.l    send_fltr       ;CDB Pointer (Long)
        dc.l    DCData3     ;DCMove Ptr (Long)
        dc.l    $00000000       ;Rqst Sense Ptr (Long)
        dc.b    $00         ;Reserved
        dc.b    $00         ;SCSI Status
        dc.b    $00         ;Command Count
        dc.l    $00000011       ;Trans Count (Long)
        dc.b    $00         ;DMA Mode
        dc.l    $00000000       ;Reserved (Long)

;*******************************************************


send_fltr   dc.b    $2A         ;Scanner SEND Command
        dc.b    $00         ;Reserved
        dc.b    $02         ;Transfer Type
        dc.b    $00         ;Reserved
        dc.b    $00         ;Reserved
        dc.b    $02         ;Transfer ID Byte
        dc.b    $00         ;Reserved
        dc.b    $00         ;Transfer Length (High)
        dc.b    $11         ;Transfer Length (Low)
        dc.b    $00         ;Reserved

;*******************************************************

DCData3 dc.l    send_data       ;Scanner SEND Data Ptr
        dc.l    $00000011       ;Transfer Count
        dc.l    $00000000       ;Offset
        dc.l    $00000000       ;Reserved

        dc.l    $00000000       ;DCStop
        dc.l    $00000000       ;Reserved
        dc.l    $00000000       ;Reserved
        dc.l    $00000000       ;Reserved

;*******************************************************

send_data   dc.b    $44         ;4 X 4 Matrix Size
        dc.b    $08         ;Pel 0
        dc.b    $88         ;Pel 1
        dc.b    $28         ;Pel 2
        dc.b    $A8         ;Pel 3
        dc.b    $C8         ;Pel 4
        dc.b    $48         ;Pel 5
        dc.b    $E8         ;Pel 6
        dc.b    $68         ;Pel 7
        dc.b    $38         ;Pel 8
        dc.b    $B8         ;Pel 9
        dc.b    $18         ;Pel 10
        dc.b    $98         ;Pel 11
        dc.b    $F8         ;Pel 12
        dc.b    $78         ;Pel 13
        dc.b    $D8         ;Pel 14
        dc.b    $58         ;Pel 15

;*******************************************************
Our scan window. Now that the scanner knows what halftone filter to use, 
we need to describe the scan window through which we'll view the 
document. Because we're using one of the Apple IIe graphics modes, our 
window will be fairly small. At 75 dpi in HiRes mode, or 150 dpi in 
Double HiRes mode, our window is about 3.75 inches across. 

For the vertical screen, we have 192 pixels. At 75 dpi, our window is 
about 2.5 inches tall. 

By using 75 dpi for HiRes and 150 dpi for Double HiRes, we can maintain 
a good aspect ratio. This allows us to display an image with minimum 
distortion. 

In our example we use Double HiRes, so we first set the resolution for 
the X axis to 150 dpi and for the Y axis to 75 dpi. Then, we set our 
scan window's upper-left corner to absolute zero. See Code Sample 4. 

;*******************************************************
;
;   CODE SAMPLE 4
;
;   In this code segment, we issue an Apple Scanner 
;   DEFINE WINDOW PARAMETERS command by using the Apple 
;   SCSI Card Generic SCSI call ($2B). This command 
;   defines the area of the scanner glass we want to scan.
;
;*******************************************************

def_window
                    ;
                    ; Issue the call.
                    ;
        lda scan_dnum
        sta dev_num4

        jsr call_card
        dc.b    $04     ;Control Call Command Number
        dc.w    cmd_list4
        rts

;*******************************************************


cmd_list4   dc.b    $03     ;PCount = 3
dev_num4    dc.b    $00     ;Device number
        dc.w    def_wndo    ;Pointer to data
        dc.b    $2B         ;Control Code

;*******************************************************

def_wndo                    ;Our Data
        dc.w    24          ;Total Length of Parms
        dc.l    def_wnd_cmd     ;CDB Pointer (Long)
        dc.l    DCData4     ;DCMove Ptr (Long)
        dc.l    $00000000       ;Rqst Sense Ptr (Long)
        dc.b    $00         ;Reserved
        dc.b    $00         ;SCSI Status
        dc.b    $00         ;Command Count
        dc.l    8+40            ;Trans Count (Long)
        dc.b    $00         ;DMA Mode
        dc.l    $00000000       ;Reserved (Long)

;*******************************************************

def_wnd_cmd dc.b    $24     ;Scanner Define Window
                            ;Parameters Command
        dc.b    $00         ;Reserved
        dc.b    $00         ;Reserved
        dc.b    $00         ;Reserved
        dc.b    $00         ;Reserved
        dc.b    $00         ;Reserved
        dc.b    $00         ;Transfer Length (High)
        dc.b    $00         ;Transfer Length (Mid)
        dc.b    8+40        ;Transfer Length (Low)
        dc.b    $80         ;Apple Bit

;*******************************************************

DCData4 dc.l    wndo_data       ;Scan Window Data Ptr
        dc.l    8+40            ;Transfer Count
        dc.l    $00000000       ;Offset
        dc.l    $00000000       ;Reserved

        dc.l    $00000000       ;DCStop
        dc.l    $00000000       ;Reserved
        dc.l    $00000000       ;Reserved
        dc.l    $00000000       ;Reserved

;*******************************************************
;   NOTE: Remember that all values longer than 1 byte 
;   are in reverse order from native 65xxx code.
;*******************************************************

wndo_data   dcb.b 6,$00     ;Reserved
        dc.b    $00         ;Transfer Length (High)
        dc.b    40          ;Transfer Length (Low)

        dc.b    $01         ;Window Identifier
        dc.b    $00         ;Reserved

        dc.b    $00         ;X Resolution (High)
        dc.b    150         ;X Resolution (Low)

        dc.b    $00         ;Y Resolution (High)
        dc.b    75          ;Y Resolution (Low)
                        ;
                        ; We will use the corner as
                        ; our upper-left position.
                        ; This is at coordinate 0,0.
                        ;
        dc.b    $00         ;Upper Left X (High)
        dc.b    $00         ;Upper Left X (Mid High)
        dc.b    $00         ;Upper Left X (Mid Low)
        dc.b    $00         ;Upper Left X (Low)

        dc.b    $00         ;Upper Left Y (High)
        dc.b    $00         ;Upper Left Y (Mid High)
        dc.b    $00         ;Upper Left Y (Mid Low)
        dc.b    $00         ;Upper Left Y (Low)
                        ;
                        ; Width is defined as the number
                        ; of 1/1200-inch increments on
                        ; the horizontal axis; must be on
                        ; a byte boundary for both the
                        ; start and end points. We will
                        ; set for 4 inches and drop the
                        ; extra.
                        ; 
        dc.b    $00         ;Width (High)
        dc.b    $00         ;Width (Mid High)
        dc.b    4*1200/256      ;Width (Mid Low)
        dc.b    4*1200      ;Width (Low)
                        ;
                        ; Length is defined as the number.
                        ; of 1/1200-inch increments on the
                        ; vertical axis. We want � 2-1/2
                        ; inches (or 3072 increments).
                        ; 
        dc.b    $00         ;Length (High)
        dc.b    $00         ;Length (Mid High)
        dc.b    3072/256        ;Length 2.56*1200 (Mid Low)
        dc.b    3072            ;Length 2.56*1200 (Low)

        dc.b    $80         ;Median Brightness
        dc.b    $80         ;Median Threshold
        dc.b    $80         ;Median Contrast
        dc.b    $01         ;Image Composition (Halftone)
        dc.b    $01         ;Bits per Pixel
        dc.b    $00         ;Halftone Mask Always $00 (High)
        dc.b    $02         ;Downloaded Mask Pattern (Low)

        dc.b    $03         ;Padding Type
        dcb.b 2,$00         ;Reserved
        dc.b    $00         ;Compression Type (None)
        dcb.b 7,$00         ;Scanner Ref. is wrong
                        ; should be 7, 
                        ; not 5.

;*******************************************************


ENGAGE SCANNER
After telling the scanner how to scan, we need to tell it to start 
scanning. See Code Sample 5. 

;*******************************************************
;
;   CODE SAMPLE 5
;
;   This code segment issues an Apple Scanner SCAN
;   command by using the Apple SCSI Card Generic SCSI
;   call ($2B). This starts the actual scanning.
;
;*******************************************************


start_scan
                    ;
                    ; Issue the call.
                    ;
        lda scan_dnum
        sta dev_num5

        jsr call_card
        dc.b    $04     ;Control Call Command Number
        dc.w    cmd_list5
        rts

;*******************************************************

cmd_list5   dc.b    $03     ;PCount = 3
dev_num5    dc.b    $00     ;Device number
        dc.w    scan_cmd    ;Pointer to data
        dc.b    $2B         ;Control Code

;*******************************************************
scan_cm                     ;Our Data
        dc.w    24          ;Total Length of Parms
        dc.l    do_scan     ;CDB Pointer (Long)
        dc.l    DCData      ;DCMove Ptr (Long)
        dc.l    $00000000   ;Rqst Sense Ptr (Long)
        dc.b    $00         ;Reserved
        dc.b    $00         ;SCSI Status
        dc.b    $00         ;Command Count
        dc.l    $00000001   ;Trans Count (Long)
        dc.b    $00         ;DMA Mode
        dc.l    $00000000   ;Reserved (Long)

;*******************************************************

do_scan dc.b    $1B     ;SCAN
                        ;Parameters Command
        dcb.b 3,$00     ;Reserved
        dc.b    1       ;Transfer Length (Low)
        dc.b    $00     ;Wait and Home Bits = 0

;*******************************************************


DCData5 dc.l    window_ID       ;Scan Window ID Ptr
        dc.l    1               ;Transfer Count
        dc.l    $00000000       ;Offset
        dc.l    $00000000       ;Reserved

        dc.l    $00000000       ;DCStop
        dc.l    $00000000       ;Reserved
        dc.l    $00000000       ;Reserved
        dc.l    $00000000       ;Reserved

;*******************************************************

window_ID   dc.b    $01         ;Window Identifier

;*******************************************************


ENERGIZING!
We can get data from the scanner in two ways. We could get it all at 
once and then manipulate it to go on the screen. In our example, we 
would need a buffer with 115,200 pixels or 14,400 bytes for the data: 
(4.0 inches * 150 dpi horizontally) * (2.56 inches * 75 dpi vertically). 


To save the amount of RAM our program uses, however, we set up a buffer 
large enough for only one line; then we read each line from the scanner 
and display it until the entire image is on the screen. See Code Sample 
6. 

The data returned by the scanner is 8 pixels per byte. Bit 7 is the 
left- most pixel and bit 0 is the right-most pixel; a value of 1 means a 
black dot in the image. In the Apple II HiRes mode, we have 7 pixels per 
byte. Bit 0 is the left-most pixel and bit 6 is the right-most pixel; a 
value of 1 means a white dot. Because the formats are different, the 
program must convert the returned data, which it does as it goes, using 
code shown in Code Sample 6. 


;
;   CODE SAMPLE 6
;
;   In this code segment, we issue a series of calls to 
;   the Apple Scanner by using the Apple SCSI Card Generic
;   SCSI call ($2B). We first issue a GET DATA STATUS
;   call to see if there is enough data. Then we read 
;   in a single scan line with a READ call. The data is 
;   then converted and placed in a video buffer.
;
;*******************************************************
get_data
        stz scan_line   ;Init the scan line to 0.
                    ;
                    ; Issue the call.
                    ;
        lda scan_dnum
        sta dev_num6
        sta dev_num65

@get_data2  jsr call_card
        dc.b    $04     ;Control Call Command Number
        dc.w    cmd_list6
        bcs @out
                    ;
                    ; Is there enough data?
                    ; Enough data = 1 scan
                    ; line of 4 inches at 150
                    ; dpi (or 600 pixels). At
                    ; 8 pixels per byte, the
                    ; data will be padded to
                    ; 75 bytes.
                    ;
        lda scan_data
        bne @have_line
        lda scan_data+1
        bne @have_line
        lda scan_data+2
        cmp #rqst_cnt   ;Decimal 75
        blt get_data
                    ;
                    ; We have the data. Read
                    ; it.
                    ;
@have_line  jsr call_card
        dc.b    $04     ;Control Call Command Number
        dc.w    cmd_list65
        bcs @out
                    ;
                    ; Now we need to invert
                    ; the data.
                    ;
        lda #80     ;80 bytes/line for Double HiRes
        sta byte_count
        stz byte_index
@loop_1 lda #$07
        sta seven       ;Pixels/byte
@loop_2 ldx #rqst_cnt-2
        asl raw_image+\
        rqst_cnt-1      ;Shift bits out the top to
@loop_3 rol raw_image,x :the next byte 1 at a time
        dex
        bpl @loop_3
        ldx byte_index  ;Shift the last bit into
        ror screen,x    ;this byte. This reverses the
        dec seven       ;bit ordering and takes 8 bits 
        bne @loop_2     ;per byte down to 7.
        lsr screen,x
        inc byte_index
        dec byte_count
        bne @loop_1
                    ;
                    ; Move data to scan line.
                    ;
        ldx scan_line
        jsr on_screen
        inc scan_line
        bra @get_data2

@out        lda #$00
        clc
        rts

;*******************************************************

scan_line   dc.b    $00     ;Scan Line Index
byte_count  dc.b    $00     ;Number of bytes left
byte_index  dc.b    $00     ;Current Byte in use
seven       dc.b    $00     ;Count off 7 pixels
screen  dcb.b 80,0      ;Place to do the screen

;*******************************************************

cmd_list6   dc.b    $03     ;PCount = 3
dev_num6    dc.b    $00     ;Device number
        dc.w    gd_status   ;Pointer to data
        dc.b    $2B         ;Control Code
cmd_list65  dc.b    $03     ;PCount = 3
dev_num65   dc.b    $00     ;Device number
        dc.w    read        ;Pointer to data
        dc.b    $2B         ;Control Code

;*******************************************************

gd_status                   ;Our Data
        dc.w    24          ;Total Length of Parms
        dc.l    get_stat    ;CDB Pointer (Long)
        dc.l    DCData6     ;DCMove Ptr (Long)
        dc.l    $00000000   ;Rqst Sense Ptr (Long)
        dc.b    $00         ;Reserved
        dc.b    $00         ;SCSI Status
        dc.b    $00         ;Command Count
        dc.l    $0000000C   ;Trans Count (Long)
        dc.b    $00         ;DMA Mode
        dc.l    $00000000   ;Reserved (Long)

read                        ;Our Data
        dc.w    24          ;Total Length of Parms
        dc.l    get_data2   ;CDB Pointer (Long)
        dc.l    DCData65    ;DCMove Ptr (Long)
        dc.l    $00000000   ;Rqst Sense Ptr (Long)
        dc.b    $00         ;Reserved
        dc.b    $00         ;SCSI Status
        dc.b    $00         ;Command Count
        dc.l    rqst_cnt    ;Trans Count (Long)
        dc.b    $00         ;DMA Mode
        dc.l    $00000000   ;Reserved (Long)

;*******************************************************

get_stat    dc.b    $34     ;GET DATA STATUS
                            ;Parameters Command
        dcb.b 7,$00         ;Reserved
        dc.b    12          ;Transfer Length (Low)
        dc.b    $00         ;Wait and Home Bits = 0

get_data2   dc.b    $28     ;READ
                            ;Parameters Command
        dcb.b 4,$00         ;Reserved
        dc.b    $01         ;Window ID
        dc.b    $00         ;Transfer Length (High)
        dc.b    $00         ;Transfer Length (Mid)
        dc.b    rqst_cnt    ;Transfer Length (Low)
        dc.b    $00         ;Wait and Home Bits = 0

;*******************************************************

DCData6 dc.l    data_cnt    ;Data Pointer
        dc.l    12          ;Transfer Count
        dc.l    $00000000   ;Offset
        dc.l    $00000000   ;Reserved

        dc.l    $00000000   ;DCStop
        dc.l    $00000000   ;Reserved
        dc.l    $00000000   ;Reserved
        dc.l    $00000000   ;Reserved

DCData65    dc.l    raw_image   ;Data Pointer
        dc.l    rqst_cnt    ;Transfer Count
        dc.l    $00000000   ;Offset
        dc.l    $00000000   ;Reserved

        dc.l    $00000000   ;DCStop
        dc.l    $00000000   ;Reserved
        dc.l    $00000000   ;Reserved
        dc.l    $00000000   ;Reserved

;*******************************************************

data_cnt                ;Data Space
        dcb.b 2,$00     ;Reserved
        dc.b    $00     ;Data Length
        dc.b    $00     ;Block
        dc.b    $00     ;Window Identifier
        dcb.b 4,$00     ;Reserved
scan_data   dc.b    $00     ;Scan Data (High)
        dc.b    $00     ;Scan Data (Mid)
        dc.b    $00     ;Scan Data (Low)

raw_image   dcb.b 100,$00   ;Scanned Data Image

;*******************************************************


PUT IT ON THE SCREEN, ENSIGN
Because we display the image in black and white, we need to set up the 
graphic soft switches accordingly. In our example, we display our image 
in HiRes Page 1, and we assume black and white display. On a color video 
monitor, the image would appear in black and white. See Code Sample 7. 

;*******************************************************
;
;   CODE SAMPLE 7
;
;   In this code segment, we toggle the HiRes soft 
;   switches so that we can see what was just scanned.
;
;*******************************************************

display
                    ;
                    ; Save the current state.
                    ;
        lda RDTEXT
        sta @text   ;Text/Graphics
        lda RDMIX
        sta @mixed  ;Mixed?

        lda RDPAGE2
        sta @page       ;Page 1 or 2

        lda RDHIRES
        sta @hires      ;HiRes Mode?

        lda RD80VID
        sta @80col      ;80-Column Mode?

        sta SET80VID    ;Set 80-Column Mode
        sta TXTCLR      ;Standard Apple II Graphics
        sta MIXCLR      ;Clear Mixed Mode
        sta TXTPAGE1    ;Page 1
        sta HIRES       ;HiRes Mode
        sta CLRAN3      ;Clear annunciator 3

        sta KBD_STRB    ;Clear Key Strobe
@key_loop   lda KBD     ;Get key
        bpl @key_loop   ;Wait for Key Press
        sta KBD_STRB    ;Clear Key Strobe
        cmp #ESC        ;ESC Key
        clc
        bne @chk_txt
        sec             ;Exit on ESC

        lda SETAN3      ;Set annunciator 3.

@chk_txt    lda @text
        bpl @chk_mix
        sta TXTSET      ;Text on

@chk_mix    lda @mixed
        bpl @chk_page
        sta MIXSET      ;Mixed on

@chk_page   lda @page
        bpl @chk_hires
        sta TXTPAGE2    ;Page 2

@chk_hires  lda @hires
        bmi @chk_40col
        sta LORES       ;HiRes Off

@chk_40col  lda @80col
        bmi @rts
        sta CLR80VID    ;80-Column on

@rts        rts

@text       dc.b    $00
@mixed      dc.b    $00
@page       dc.b    $00
@hires      dc.b    $00
@80col      dc.b    $00

;*******************************************************


FILE THE REPORT AND HEAD FOR HOME
Now, save the image in its displayable format. Save it as you would any 
file, using standard ProDOS MLI calls. 

FINAL LOG ENTRY
The ability to bring printed images into the computer opens up many 
possibilities for you and for your customers. Programs that use graphics 
can import and add color to printed images. For example, users can put 
together files that include family photos. These files can then be 
transmitted electronically to others for viewing. 

You can also give users control over a number of scan parameters. For 
example, you could allow them to position the scan window on a graphic 
representation of the scanner glass; users could then position the scan 
without adjusting the printed page on the scanner glass. Or you could 
allow users to specify the resolution of the scan, showing them how the 
scan window size changes. 

Although not demonstrated here, Line Art mode provides very clean images 
of scanned text. If you use Line Art mode to support optical character 
recognition (OCR), users can import text and avoid retyping entire 
manuscripts. 

The possibilities are endless. Have fun exploring them. That is, after 
all, what it is all about--doing more with your Apple II and having fun 
doing it. 
THE SCANNING PROCESS


The scanning process involves five steps for your application, described 
briefly below. For general information about scanner technology and 
terminology, see the Apple Scanner Reference. 

1. Initialize the scanner parameters
You must set the scanner parameters before you start a scan. These 
parameters determine how much space the image needs. 
Use these commands:
    MODE SENSE ($1A)
    MODE SELECT ($15)
    SEND ($2A)
    DEFINE WINDOW PARAMETERS ($24)


2. Define an image buffer
The image buffer is free memory within the computer system that holds 
the bitmap image returned by the scanner. The size of the buffer 
dictates the amount of data you can retrieve from the scanner and thus 
the size of the image. If an image is larger than the available free 
memory, you can spool it to disk for later retrieval. 

3. Start the scan
After you set the parameters, you can issue a scanner command to start 
scanning. When the scanner receives this command, it scans the image and 
places it in its internal memory. 
Use this command:  SCAN ($1B)


4. Request the scanned data
You must read the image from the scanner as it is placed in the 
scanner's internal memory. Because the scanner's memory can hold only a 
small portion of the image being scanned, and because you must read the 
data to allow the scan to continue, you should poll the scanner 
promptly. 
Use these commands:
    GET DATA STATUS ($34)
    READ ($28)


5. Save the image to a file
You can save the data in a number of formats: HiRes and Double HiRes for 
the Apple II family, Super HiRes for the Apple IIGS, and PICT or any 
other Macintosh image format. You can also store the data in other 
formats, such as GIF. The choice is yours. 

MATTHEW GULICK According to his business cards, Matt Gulick is an 
all-around SCSI (say it out loud) guy--who hates to shave and refuses to 
wear shoes except when meeting with someone with a title of VP or 
higher. He dearly loves the strict dress code, highly regimented working 
hours, and totally controlled environment at Apple. His career here was 
preordained by his being "genetically defective at birth." This 
condition first visibly manifested itself at age 12 when he began 
reading computer punch cards for fun. He did temporarily buck his 
computer industry destiny by studying pre-vet medicine at Brigham Young 
University. However, after college he got back on track by working as an 
"electronic stuff" sales rep, and then he programmed for ParaMIS. Now he 
feels he's running the perfect scam: getting paid to play with 
computers. A member of the Dr. Demento Fan Club (DDFC), he fears his 
wife will sue him for dementing his four children, who only know the 
Weird Al versions of song lyrics. * 

You should let users adjust the settings for Brightness, Threshold, and 
Contrast so they can customize the scan to the type of image being 
scanned (black and white or color; printed page or photo). If you let 
users choose Line Art or Grayscale, they can also optimize the scan for 
text or for an image. * 

--------------------
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