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VDriveZ88.asm
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VDriveZ88.asm
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module VDriveZ88
include "director.def"
include "dor.def"
include "stdio.def"
include "serintfc.def"
include "syspar.def"
include "fileio.def"
include "error.def"
include "memory.def"
include "integer.def"
include "time.def"
include "fpp.def"
include "vdap.def"
; General constants
defc port_timeout_default = 25 ; 1/4 second
defc port_timeout_long = 50 ; 1/2 second
defc filename_length = 20
defc dir_item_width = 14
defc dir_cols = 6
defc dir_rows = 7
defc dir_left = 0
defc dir_top = 0
defc dir_right = dir_left + dir_item_width * dir_cols
defc dir_bottom = dir_top + dir_rows
; Unsafe workspace variables
defc unsafe_ws = 152
defc safe_ws = 0
defc ram_vars = $1FFE - unsafe_ws
defvars ram_vars {
screen_handle ds.w 1 ; screen handle
port_handle ds.w 1 ; serial port handle
port_timeout ds.w 1 ; serial port timeout
file_handle ds.w 1 ; file handle
filename ds.b 32 ; buffer for filenames
has_disk ds.b 1 ; whether the drive has a disk in it or not
memory_pool ds.w 1 ; memory allocation pool
dir_list ds.w 2 ; pointer to first file in list
dir_count ds.w 1 ; number of files in file list
dir_list_ptr ds.w 2 ; pointer to current item in file list
dir_list_new ds.w 2 ; pointer to new item in the file list
dir_list_old ds.w 2 ; pointer to old item in the file list
cursor_x ds.b 1 ; cursor x
cursor_y ds.b 1 ; cursor y
dir_offset ds.w 1 ; offset into directory listing
dir_working ds.w 1 ; working file index
dir_selected ds.w 1 ; selected file index
path ds.w 2 ; pointer to storage for full file path
file_size ds.b 4 ; size of a file
file_created ds.w 2 ; file creation date+time
file_accessed ds.w 2 ; file accessed date+time
file_modified ds.w 2 ; file modification date+time
oz_date_time ds.b 6 ; OZ-format date+time
local_filename ds.b 32 ; local filename for copy operations
file_buffer ds.w 2 ; allocated buffer to handle file transfers
data_transferred ds.b 4 ; general "data remaining" counter
data_remaining ds.b 4 ; general "data remaining" counter
chunk_size ds.w 2 ; when transferring data to/from the drive
old_pa_txb_size ds.b 1 ; transmit baud rate is 1 or 2 bytes
old_pa_txb ds.w 1 ; original transmit baud rate
old_pa_rxb_size ds.b 1 ; receive baud rate is 1 or 2 bytes
old_pa_rxb ds.w 1 ; original receive baud rate
old_pa_xon ds.b 1 ; original xon/off state
old_pa_par ds.b 1 ; original parity state
ram_vars_end ds.b 1
}
if ram_vars_end - ram_vars > unsafe_ws
error "Too many variables"
endif
; Application bank and origin
defc appl_bank = $3F ; default to top bank loading
org $E000
; Application DOR
.appl_dor
defb 0,0,0 ; links to parent, brother, son
defb 0,0,0
defb 0,0,0
defb $83 ; DOR type - application
defb indorend-indorstart
.indorstart
defb '@' ; key to info section
defb ininfend-ininfstart
.ininfstart
defw 0
defb 'D' ; application key
defb 0 ; no bad app memory
defw 0 ; overhead
defw unsafe_ws ; unsafe workspace
defw safe_ws ; safe workspace
defw appl_start ; entry point
defb 0 ; bank bindings
defb 0
defb 0
defb appl_bank
defb at_popd|at_good ; good popdown
defb 0 ; no caps lock
.ininfend
defb 'H' ; key to help section
defb inhlpend-inhlpstart
.inhlpstart
defw topics_dor
defb appl_bank
defw commands_dor
defb appl_bank
defw help_dor
defb appl_bank
defw tokens_dor
defb appl_bank
.inhlpend
defb 'N' ; key to name section
defb innamend-innamstart
.innamstart
defm "VDrive", 0
.innamend
defb $FF
.indorend
.topics_dor
defb 0 ; start marker
.topic_commands
defb topic_end - topic_commands ; length byte
defm "Commands" ; topic name
defb >(help_commands - help_dor) ; help offset msb
defb <(help_commands - help_dor) ; help offset lsb
defb TPCF_HELP ; topic attributes
defb topic_end - topic_commands ; length byte
.topic_end
defb 0 ; end marker
.commands_dor
defb 0 ; start marker
.cmd_rename
defb cmd_rename_end - cmd_rename ; length byte
defb 'R' ; command code
defm "RE", 0 ; keyboard sequence
defm "Rename" ; command name
defb >(help_rename - help_dor) ; help offset msb
defb <(help_rename - help_dor) ; help offset lsb
defb CMDF_HELP ; command attributes
defb cmd_rename_end - cmd_rename ; length byte
.cmd_rename_end
.cmd_erase
defb cmd_erase_end - cmd_erase ; length byte
defb 'E' ; command code
defm "ER", 0 ; keyboard sequence
defm "Erase" ; command name
defb >(help_erase - help_dor) ; help offset msb
defb <(help_erase - help_dor) ; help offset lsb
defb CMDF_HELP ; command attributes
defb cmd_erase_end - cmd_erase ; length byte
.cmd_erase_end
.cmd_create
defb cmd_create_end - cmd_create ; length byte
defb 'C' ; command code
defm "CD", 0 ; keyboard sequence
defm "Create Directory" ; command name
defb >(help_create - help_dor) ; help offset msb
defb <(help_create - help_dor) ; help offset lsb
defb CMDF_HELP ; command attributes
defb cmd_create_end - cmd_create ; length byte
.cmd_create_end
.cmd_up_dir
defb cmd_up_dir_end - cmd_up_dir ; length byte
defb IN_SUP ; command code
defm IN_SUP, 0 ; keyboard sequence
defm "Up Directory" ; command name
defb >(help_up_dir - help_dor) ; help offset msb
defb <(help_up_dir - help_dor) ; help offset lsb
defb CMDF_COLUMN|CMDF_HELP ; command attributes
defb cmd_up_dir_end - cmd_up_dir ; length byte
.cmd_up_dir_end
.cmd_dwn_dir
defb cmd_dwn_dir_end - cmd_dwn_dir ; length byte
defb IN_SDWN ; command code
defm IN_SDWN, 0 ; keyboard sequence
defm "Down Directory", 0 ; command name
defb >(help_dwn_dir - help_dor) ; help offset msb
defb <(help_dwn_dir - help_dor) ; help offset lsb
defb CMDF_HELP ; command attributes
defb cmd_dwn_dir_end - cmd_dwn_dir ; length byte
.cmd_dwn_dir_end
.cmd_cur_rgt
defb cmd_cur_rgt_end - cmd_cur_rgt ; length byte
defb IN_RGT ; command code
defm IN_RGT, 0 ; keyboard sequence
defm "Cursor Right", 0 ; command name
defb cmd_cur_rgt_end - cmd_cur_rgt ; length byte
.cmd_cur_rgt_end
.cmd_cur_lft
defb cmd_cur_lft_end - cmd_cur_lft ; length byte
defb IN_LFT ; command code
defm IN_LFT, 0 ; keyboard sequence
defm "Cursor Left", 0 ; command name
defb cmd_cur_lft_end - cmd_cur_lft ; length byte
.cmd_cur_lft_end
.cmd_cur_up
defb cmd_cur_up_end - cmd_cur_up ; length byte
defb IN_UP ; command code
defm IN_UP, 0 ; keyboard sequence
defm "Cursor Up", 0 ; command name
defb cmd_cur_up_end - cmd_cur_up ; length byte
.cmd_cur_up_end
.cmd_cur_dwn
defb cmd_cur_dwn_end - cmd_cur_dwn ; length byte
defb IN_DWN ; command code
defm IN_DWN, 0 ; keyboard sequence
defm "Cursor Down", 0 ; command name
defb cmd_cur_dwn_end - cmd_cur_dwn ; length byte
.cmd_cur_dwn_end
.cmd_send
defb cmd_send_end - cmd_send ; length byte
defb 'S' ; command code
defm "ES", 0 ; keyboard sequence
defm "Send to Drive" ; command name
defb >(help_send - help_dor) ; help offset msb
defb <(help_send - help_dor) ; help offset lsb
defb CMDF_COLUMN|CMDF_HELP ; command attributes
defb cmd_send_end - cmd_send ; length byte
.cmd_send_end
.cmd_fetch
defb cmd_fetch_end - cmd_fetch ; length byte
defb 'F' ; command code
defm "EF", 0 ; keyboard sequence
defm "Fetch from Drive" ; command name
defb >(help_fetch - help_dor) ; help offset msb
defb <(help_fetch - help_dor) ; help offset lsb
defb CMDF_HELP ; command attributes
defb cmd_fetch_end - cmd_fetch ; length byte
.cmd_fetch_end
defb 1 ; end of topic
defb 0 ; end of all topics
.help_dor
defm DEL
defm "Version 1.0", DEL
defm DEL
defm "Send files to and fetch files from a Vinculum", DEL
defm "USB host device such as the VDrive or VMusic.", DEL
defm DEL
defm "Ben Ryves 2023 - https://benryves.com/", 0
.help_commands
defm "The current directory listing will be shown with directories", DEL
defm "at the top in small capitals (", SOH, "2+TDIRNAME", SOH, "2-T) and files underneath.", DEL
defm "You can move around the listing using the ", TOK_CURSOR_KEYS, " keys,", DEL
defm "enter directories or fetch files with the ", TOK_ENTER, " key,", DEL
defm "or erase files with the ", TOK_DEL, " key.", DEL
defm "Other operations can be accessed with the ", TOK_MENU, " key.", 0
.help_rename
defm DEL
defm "Rename existing files or directories on the USB drive.", 0
.help_erase
defm DEL
defm "Erase existing files or directories from the USB drive.", DEL
defm DEL
defm "Directories that contain other items cannot be erased,", DEL
defm "so make sure to empty them before erasing them.", DEL
defm DEL
defm "Files or directories can also be erased with the ", TOK_DEL, " key.", 0
.help_create
defm DEL
defm "Create a new directory on the USB drive.", 0
.help_up_dir
defm DEL
defm "Move up to the parent directory of the current directory.", 0
.help_dwn_dir
defm DEL
defm "Move down into the highlighted child directory.", DEL
defm DEL
defm "You can also enter child directories by highlighting them", DEL
defm "and pressing the ", TOK_ENTER, " key.", 0
.help_send
defm DEL
defm "Send a file from the Z88's file system to the", DEL
defm "current directory on the USB drive.", 0
.help_fetch
defm DEL
defm "Fetch the highlighted file from the USB drive and save it", DEL
defm "on the Z88's file system.", DEL
defm DEL
defm "You can also fetch files by highlighting them and pressing", DEL
defm "the ", TOK_ENTER, " key.", 0
.tokens_dor
defb (token_80 - tokens_list) / 2
defb (token_80 - tokens_list) / 2
.tokens_list
defw token_80 - tokens_dor
defw token_81 - tokens_dor
defw token_82 - tokens_dor
defw token_83 - tokens_dor
defw tokens_end - tokens_dor
.token_80
defm SOH, SD_ENT
.token_81
defm SOH, SD_DEL
.token_82
defm SOH, SD_ORGT, SOH, SD_OLFT, SOH, SD_OUP, SOH, SD_ODWN
.token_83
defm SOH, SD_MNU
.tokens_end
defc TOK_ENTER = $80
defc TOK_DEL = $81
defc TOK_CURSOR_KEYS = $82
defc TOK_MENU = $83
; The main entry point
.appl_start
jp appl_main
scf
ret
.appl_main
; clear our RAM variables
ld hl, ram_vars
ld (hl), 0
ld de, ram_vars + 1
ld bc, unsafe_ws - 1
ldir
; back up original panel settings
ld a, 2
ld bc, PA_Txb
ld de, old_pa_txb
oz (OS_Nq)
jr c, bye_error
ld (old_pa_txb_size), a
ld a, 2
ld bc, PA_Rxb
ld de, old_pa_rxb
oz (OS_Nq)
jr c, bye_error
ld (old_pa_rxb_size), a
ld a, 1
ld bc, PA_Xon
ld de, old_pa_xon
oz (OS_Nq)
jr c, bye_error
ld a, 1
ld bc, PA_Par
ld de, old_pa_par
oz (OS_Nq)
jr c, bye_error
; use segment 1 for memory allocations
ld a, MM_S1
ld bc, 0
oz (OS_Mop)
jr nc, opened_pool
; quit with error message
.bye_error
oz (GN_Err)
oz (OS_Bye)
.opened_pool
ld (memory_pool), ix
; allocate memory for the path
xor a
ld bc, 256
oz (OS_Mal)
jp c, appl_exit
ld (path + 0), bc
ld (path + 2), hl
oz (OS_Mpb)
ld (hl), 0
; allocate memory for the file transfer buffer
xor a
ld bc, 256
oz (OS_Mal)
jp c, appl_exit
ld (file_buffer + 0), bc
ld (file_buffer + 2), hl
; open the screen from its name
ld bc, filename_length
ld hl, screen_name
ld de, filename
ld a, OP_UP
oz (GN_Opf)
jp c, appl_exit
; store the port handle
ld (screen_handle), ix
; initialise the full window for output
ld hl, window_full
oz (GN_Sop)
; initialise the drive
call drive_init
ld hl, connecting
oz (GN_Sop)
.connecting_loop
call sync
jr c, connecting_failed
jr z, connecting_succeeded
.connecting_failed
ld bc, 10
oz (OS_Tin)
jr nc, connecting_loop_key
cp RC_TIME
jr z, connecting_loop
jp appl_exit
.connecting_loop_key
cp ESC
jp z, appl_exit
jr connecting_loop
.connecting_succeeded
ld hl, ok
oz (GN_Sop)
oz (Gn_Nln)
call busy_start
; path is already cleared, so just skip to the root directory
ld hl, up_to_root
call change_directory
; clear the screen
ld hl, window_full
oz (GN_Sop)
call busy_end
; skip the next block as we've already reset the path
jr dir_list_start
.dir_list_start_from_current
call busy_start
call dir
call busy_end
jr dir_list_start
.dir_list_start_from_root
; clear the stored path
ld bc, (path + 0)
ld hl, (path + 2)
oz (OS_Mpb)
ld (hl), 0
call busy_start
; initially start from the root directory
ld hl, up_to_root
call change_directory
call busy_end
.dir_list_start
; draw the title bar
ld hl, window_title_begin
oz (GN_Sop)
ld a, (has_disk)
or a
jr nz, dir_list_title_path
ld hl, no_disk
jr dir_list_output_title
.dir_list_title_path
ld hl, path_prefix
oz (GN_Sop)
ld bc, (path + 0)
ld hl, (path + 2)
oz (OS_Mpb)
.dir_list_output_title
oz (GN_Sop)
ld hl, window_title_end
oz (GN_Sop)
; switch to the directory window
ld hl, window_dir
oz (GN_Sop)
; ensure it's ungreyed
call ungrey_window
.dir_list_render
ld hl, (dir_count)
ld a, l
or h
jp z, key_loop
.dir_list_has_files
ld a, dir_left
ld (cursor_x), a
ld a, dir_top
ld (cursor_y), a
.dir_list_selection_on_screen_check
; ensure that the selected index is on-screen
ld hl, (dir_selected)
ld de, (dir_offset)
or a
sbc hl, de
bit 7, h
jr nz, dir_list_selection_off_top
ld de, dir_cols * dir_rows
or a
sbc hl, de
jr c, dir_list_selection_on_screen
.dir_list_selection_off_bottom
; increment the offset
ld hl, (dir_offset)
ld de, +dir_cols
add hl, de
ld (dir_offset), hl
jr dir_list_selection_on_screen_check
.dir_list_selection_off_top
; decrement the offset
ld hl, (dir_offset)
ld de, -dir_cols
add hl, de
ld (dir_offset), hl
jr dir_list_selection_on_screen_check
.dir_list_selection_on_screen
ld de, (dir_offset)
ld (dir_working), de
call dir_set_index
.dir_list_loop
call dir_list_print_file
jr z, dir_list_done
call dir_next
jr nz, dir_list_loop
.dir_list_done
; we've either run out of files/directories to display,
; or we've filled the screen
xor a
ld (cursor_x), a
ld (cursor_y), a
.no_dir_list
; wait for key
.key_loop
call check_events
jr z, no_key_loop_events
; there was an event
jp dir_list_start_from_root
.no_key_loop_events
ld bc, 100
oz (OS_Tin)
jr c, key_error
or a
jr z, extended_key
cp ESC
jp z, appl_exit
cp CR
jp z, dir_enter
cp DEL
jp z, delete_file
; if it's a filename character, can we jump to the next file starting with its initial?
call char_to_upper
call validate_filename_char
jr c, key_loop
; jump to next item starting with the initial just pressed
ld c, a
ld hl, (dir_count)
ld a, h
or l
jr z, key_loop
; start from the current file
push bc
ld de, (dir_selected)
ld (dir_working), de
call dir_set_index
pop bc
.next_lettered_file_loop
; advance to the next file
push bc
ld de, (dir_working)
inc de
push de
call dir_next
pop de
jr nz, next_lettered_file_nowrap
call dir_reset_index
ld de, 0
.next_lettered_file_nowrap
ld (dir_working), de
pop bc
; does the file start with our desired character?
ld de, 4 + 1
add hl, de
ld a, (hl)
cp c
jr z, next_lettered_file_found
; have we looped around?
ld hl, (dir_working)
ld de, (dir_selected)
or a
sbc hl, de
jr nz, next_lettered_file_loop
.next_lettered_file_found
; how far have we moved?
ld hl, (dir_working)
ld de, (dir_selected)
or a
sbc hl, de
jr z, key_loop
ex de, hl
jp dir_move_16
.key_error
; time-outs are OK
cp RC_TIME
jp z, key_loop
cp RC_SUSP
jp z, key_loop
cp RC_DRAW
jp z, dir_list_start
; treat any other errors as a request to quit
jp appl_exit
.extended_key
oz (OS_In)
jr c, key_error
cp 'R'
jp z, rename_file
cp 'E'
jp z, delete_file
cp 'C'
jp z, create_dir
cp IN_SUP
jp z, dir_up_a_level
cp IN_SDWN
jp z, dir_down_a_level
cp IN_RGT
jr z, dir_move_right
cp IN_LFT
jr z, dir_move_left
cp IN_UP
jr z, dir_move_up
cp IN_DWN
jr z, dir_move_down
cp 'S'
jp z, send_file
cp 'F'
jp z, dir_fetch
jp key_loop
.dir_list_print_file
; set cursor position
call goto_cursor
ld a, ' '
oz (OS_Out)
; show file name
ld bc, (dir_list_ptr + 0)
ld hl, (dir_list_ptr + 2)
oz (OS_Mpb)
ld bc, 4
add hl,bc
; first character of name denotes if it's 'f' file or 'd' directory
ld a, (hl)
inc hl
cp 'd'
jr nz, dir_list_is_file
; enable directory style
push hl
ld hl, working_file_is_dir
oz (GN_Sop)
pop hl
.dir_list_is_file
oz (GN_Sop)
; switch back to default file styles
ld hl, working_file_is_file
oz (GN_Sop)
; advance file position, but also check if it was the selected file
ld hl, (dir_selected)
ld de, (dir_working)
or a
sbc hl, de
inc de
ld (dir_working), de
jr nz, dir_list_not_selected
; if the file was selected, apply the reverse video style
call goto_cursor
ld hl, selected_file_reverse_on
oz (GN_Sop)
.dir_list_not_selected
; advance cursor position
ld a, (cursor_x)
add a, dir_item_width
cp dir_right
jr nz, dir_list_cursor_done
ld a, (cursor_y)
inc a
ld (cursor_y), a
cp dir_bottom
ret z
ld a, dir_left
.dir_list_cursor_done
ld (cursor_x), a
cp $FF ; force nz
ret
.dir_move_left
ld a, -1
jr dir_move
.dir_move_right
ld a, +1
jr dir_move
.dir_move_up
ld a, -dir_cols
jr dir_move
.dir_move_down
ld a, +dir_cols
jr dir_move
.dir_move
; sign-extend a -> de
ld e, a
add a, a
sbc a, a
ld d, a
.dir_move_16
; can't move within the directory listing if there aren't any files
ld hl, (dir_count)
ld a, h
or l
jp z, dir_move_skip
; can't move within the directory listing if there's just one file too
dec hl
ld a, h
or l
jp z, dir_move_skip
push de
call goto_selected_file
ld hl, selected_file_reverse_off
oz (GN_Sop)
pop de
ld hl, (dir_selected)
add hl, de
bit 7, h
jr z, dir_move_not_off_start
ld hl, (dir_count)
dec hl
.dir_move_not_off_start
ld (dir_selected), hl
ld de, (dir_count)
or a
sbc hl, de
jr c, dir_move_not_off_end
ld hl, 0
ld (dir_selected), hl
.dir_move_not_off_end
; have we moved off the top or bottom of the screen?
.dir_move_off_edge_loop
ld hl, (dir_selected)
ld de, (dir_offset)
or a
sbc hl, de
bit 7, h
jr nz, dir_moved_off_top
ld de, dir_cols * dir_rows
or a
sbc hl, de
jr c, dir_move_not_off_bottom
; increment the offset
ld hl, (dir_offset)
ld de, +dir_cols
add hl, de
ld (dir_offset), hl
; scroll the screen
ld a, SOH
oz (OS_Out)
ld a, SD_DWN
oz (OS_Out)
; redraw the bottom line of files
ld hl, (dir_offset)
ld de, dir_cols * [ dir_rows - 1 ]
add hl, de
ex de, hl
ld (dir_working), de
call dir_set_index
ld a, dir_left
ld (cursor_x), a
ld a, dir_bottom - 1
ld (cursor_y), a
.dir_move_off_bottom_reprint_loop
call dir_list_print_file
jr z, dir_move_off_edge_loop
call dir_next
jr nz, dir_move_off_bottom_reprint_loop
jr dir_move_off_edge_loop
.dir_moved_off_top
; decrement the offset
ld hl, (dir_offset)
ld de, -dir_cols
add hl, de
ld (dir_offset), hl
; scroll the screen
ld a, SOH
oz (OS_Out)
ld a, SD_UP
oz (OS_Out)
; redraw the top line of files
ld de, (dir_offset)
ld (dir_working), de
call dir_set_index
ld a, dir_left
ld (cursor_x), a
ld a, dir_top
ld (cursor_y), a
ld b, dir_cols
.dir_move_off_top_reprint_loop
push bc
call dir_list_print_file
pop bc
jr z, dir_move_off_edge_loop
push bc
call dir_next
pop bc
jp z, dir_move_off_edge_loop
djnz dir_move_off_top_reprint_loop
jp dir_move_off_edge_loop
.dir_move_not_off_bottom