148 lines
5.2 KiB
ArmAsm
148 lines
5.2 KiB
ArmAsm
; Names of ZP and low memory locations
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; (Only those for now that we feel the need to implement initially)
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; (https://www.c64-wiki.com/wiki/Zeropage)
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.alias tokenise_work1 $7
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.alias tokenise_work2 $8
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.alias tokenise_work3 $B
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.alias tokenise_work4 $F
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.alias basic_line_number $14
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.alias temp_string_ptr $35
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.alias load_or_verify_or_tokenise_work5 $C
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.alias basic_work22 $22
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.alias basic_work23 $23
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.alias basic_work24 $24
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.alias basic_work25 $25
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;; The various pointers that separate memory regions for BASIC storage
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;; We have multiple names for the ones that mark the boundary of regions.
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.alias basic_start_of_text_ptr $2b
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.alias basic_end_of_text_ptr $2d
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.alias basic_start_of_vars_ptr $2d
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.alias basic_end_of_vars_ptr $2f
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.alias basic_start_of_arrays_ptr $2f
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.alias basic_end_of_arrays_ptr $31
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.alias basic_start_of_free_space_ptr $31
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.alias basic_start_of_strings_ptr $33
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.alias basic_top_of_memory_ptr $37
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.alias basic_current_line_number $39
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.alias basic_previous_line_number $3b
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.alias basic_current_line_ptr $3d
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;; Note that the statement point is in the CHRGET/CHRGOT routine
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;; in ZP RAM. (Compute's Mapping the 64, p25)
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.alias basic_current_statement_ptr $7a
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.alias basic_numeric_work_area $57 ; $57 - $60 inclusive = 10 bytes
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;; Floating point accumulator 1 $61 - $68
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.alias basic_fac1_exponent $61
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.alias basic_fac1_mantissa $62 ; $62 - $65
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.alias basic_fac1_sign $66
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.alias basic_fac1_overflow $68
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.alias basic_fac1_mantissa_lob $70
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.alias basic_fac2_exponent $69
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.alias basic_fac2_mantissa $6A ; $6A - $6D
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.alias basic_fac2_sign $6E
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;; We also re-use FAC2 for memory move pointers, since
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;; we can't be doing calculations while moving memory
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.alias memmove_src $69
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.alias memmove_dst $6b
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.alias memmove_size $6d
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.alias TXTTAB $2B
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.alias IOSTATUS $90
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; Keys down clears bits. STOP=bit 7, C= bit 6, SPACE bit 4, CTRL bit 2
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.alias BUCKYSTATUS $91
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.alias load_or_verify_flag $93
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.alias current_file_num $98
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.alias input_device_number $99
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; bit 6 = error messages, bit 7 = control messages
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.alias kernal_message_control_flags $9d
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.alias jiffy_clock_24bits $a0
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.alias cassette_buffer_bytes_used $A6
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.alias load_or_scroll_temp_pointer $AC
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;; We also use the following for temp colour pointer when scrolling
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.alias load_save_verify_end_address $AE
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.alias cassette_buffer_ptr $B2
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.alias current_filename_length $B7
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.alias current_logical_filenum $B8
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.alias current_secondary_address $B9
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.alias current_device_number $BA
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.alias current_filename_ptr $BB
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.alias load_save_start_ptr $C1
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.alias load_save_end_ptr $C3
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.alias last_key_matrix_position $C5
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.alias keys_in_key_buffer $C6
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.alias reverse_video_flag $C7
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.alias end_of_input_line $C8
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.alias start_of_keyboard_input $C9
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.alias current_key_index_entry $CB
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.alias cursor_blink_disable $CC
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.alias cursor_blink_countdown $CD
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.alias cursor_saved_character $CE
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.alias cursor_is_visible $CF
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.alias keyboard_input_ready $D0
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.alias current_screen_line_ptr $D1
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.alias current_screen_x $D3
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.alias quote_mode_flag $D4
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.alias logical_line_length $D5
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.alias current_screen_y $D6
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.alias last_printed_character_ascii $D7
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.alias insert_mode $D8
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; Bits 0 -3 = bits 8-11 of screen line address
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; Bit 7 = line spans multiple physical lines
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.alias screen_line_link_table $D9
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.alias current_screen_line_colour_ptr $F3
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.alias keyboard_decoding_table_ptr $F5
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.alias rs232_rx_buffer_ptr $F7
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.alias rs232_tx_buffer_ptr $F9
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.alias basic_input_buffer $0200
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; "Compute's Mapping the 64" book
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.alias keyboard_buffer $0277
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.alias MEMSTR $0281
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.alias MEMSIZ $0283 ; NOTE: Mapping the 64 erroniously has the hex as $282, while the DEC is correct
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.alias text_colour $0286 ; p55
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.alias colour_under_cursor $0287 ; p56
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.alias HIBASE $0288 ; p56 (high byte of start of screen)
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.alias key_buffer_size $0289 ; p57
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;; 0 = cursor keys, insert, delete and space repeat, but nothing else
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;; 128 = all keys repeat
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;; 64 = no keys repeat
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.alias key_repeat_flags $028A ; p58
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;; https://www.c64-wiki.com/wiki/Page_2
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.alias key_repeat_counter $028B
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.alias key_first_repeat_delay $028C
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;; bit 0 = shift, 1 = Vendor Key, 2 = Control
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.alias key_bucky_state $028D
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.alias key_last_bucky_state $028E
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.alias keyboard_decoding_ptr $028F
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.alias enable_case_switch $0291
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.alias screen_scroll_disable $0292
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.alias pal_or_ntsc $02A6
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;; Registers for SYS call
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.alias sys_reg_a $30c
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.alias sys_reg_x $30d
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.alias sys_reg_y $30e
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.alias sys_reg_p $30f
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.alias sys_jmp $310
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;; BASIC uses some extra bytes for memory access under ROMs located at $2A7 onwards
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;; IRQs are disabled when doing such accesses, and a default NMI handler only increments
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;; a counter, so that if an NMI occurs, it doesn't crash the machine, but can be captured.
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.alias missed_nmi_flag $2A7
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.alias tiny_nmi_handler $2A8
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.alias shift_mem_up tiny_nmi_handler+shift_mem_up_routine-tiny_nmi_handler_routine
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.alias shift_mem_down tiny_nmi_handler+shift_mem_down_routine-tiny_nmi_handler_routine
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.alias peek_under_roms tiny_nmi_handler+peek_under_roms_routine-tiny_nmi_handler_routine
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.alias poke_under_roms tiny_nmi_handler+poke_under_roms_routine-tiny_nmi_handler_routine
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.alias memmap_allram tiny_nmi_handler+memmap_allram_routine-tiny_nmi_handler_routine
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.alias memmap_normal tiny_nmi_handler+memmap_normal_routine-tiny_nmi_handler_routine
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