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Acorn ANFS 4.18 Memory Map

← Acorn NFS and Acorn ANFS

Addresses outside the ROM used by Acorn ANFS 4.18 at run time — zero-page workspace, RAM buffers, and memory-mapped I/O. For the ROM code itself (&8000–&BFFF), see the disassembly listing.

Access: R read, W write, B indexing base — the address is named as base,X/,Y, so the byte actually touched is base + index and the literal byte at this address is never itself accessed.

Zero page

Address Name Access Description
&0002 zp_work_2 B
&0003 zp_work_3 B
&00C2 txcb_dest B
&00C7 txcb_pos B
&00ED tx_imm_idx_base B

6502 stack page

Address Name Access Description
&0102 stack_page_2 B
&0103 stack_page_3 B
&0104 stack_page_4 B
&0106 stack_page_6 B
&0128 tube_osword_pb B

RAM workspace

Address Name Access Description
&02A0 rom_type_table B
&0700 string_buf B
&0CFF nmi_code_base B
&0D1A imm_param_base B
&0D1E tx_addr_base B
&0D26 tx_data_start B
&0D32 scout_data B
&0DE6 txcb_default_base B
&0DF0 rom_ws_pages B
&0DFE osword_ws_base B
&0DFF fs_server_base B
&0E2F fs_filename_buf_m1 B
&0E38 fs_filename_backup B
&0EF7 fs_reply_data B
&0F0D fs_file_len B
&0FC8 channel_status_table B
&0FE0 fcb_xfer_count_lo B
&0FF0 fcb_xfer_count_mid B
&0FFF print_str_idx_base B
&1000 fcb_count_lo B
&1010 fcb_attr_or_count_mid B
&1020 fcb_station_or_count_hi B
&1030 fcb_net_or_port B
&1040 fcb_flags B
&1050 fcb_net_num B
&1060 chan_status B
&1078 fcb_stn_lo B
&1088 fcb_stn_hi B
&1098 fcb_buf_offset B
&10A8 fcb_attr_ref B
&10B8 fcb_status B
&10D1 xfer_counter B
&10D9 fcb_ctx_save B
&10F3 filename_buf B

Indexing-base addresses (wrap into ZP)

Address Name Access Description
&FFB0 nmi_buf_idx_base B
&FFBD fcb_workspace_idx_base B