head 1.1; branch 1.1.1; access; symbols t1641:1.1.1.2 T070803:1.1.1.1 APERT:1.1.1; locks; strict; comment @# @; 1.1 date 2003.08.07.09.47.40; author armando; state Exp; branches 1.1.1.1; next ; 1.1.1.1 date 2003.08.07.09.47.40; author armando; state Exp; branches; next 1.1.1.2; 1.1.1.2 date 2003.08.11.14.38.56; author armando; state Exp; branches; next ; desc @@ 1.1 log @Initial revision @ text @; FAT16 READER V.050303 - Armando Astarloa - 16 BIT VER. ; APERT - UPV/EHU 2003 - DISTRIBUTED UNDER GPL LICENCE ; ; s0 -> TMP0 s1 -> TMP1 s2 -> TMP2 s3 -> TMP3 s4 -> TMP4 / SECTORS_PER_CLUSTER_READED s5 -> TMP5/SECTOR_WORDS_READED (256 TO 0) ; s6 -> TMP s7 -> SECTORS_PER_CLUSTER s8 -> CLUSTER_BEGIN_LBA0 (FAT) s9 -> CLUSTER_BEGIN_LBA1 sA -> CLUSTER_BEGIN_LBA2 ; sB -> CLUSTER_BEGIN_LBA3 sC -> ROOT_DIRECTORY_FIRST_CLUSTER0 (SUPPOSED LESS THAN 256 - USUALLY 2) ; sD -> data[7:0] WB MASTER sE -> data[15:8] WB MASTER sF -> acummulator CONSTANT DATA_WB_OUT_7_0_MASTER,00 CONSTANT DATA_WB_OUT_15_8_MASTER,01 CONSTANT CONTROL_WB_OUT_MASTER,02 ; D7 = D6 = D5 = D4 = D3 = D2 = A0_MASTER D1 = W_WE_MASTER D0 = STB_O_MASTER ; STROBE_O_MASTER = 1 & W_WE=0 & WB_A0 = 0 CONSTANT READ_SLAVE,01 ; STROBE_O_MASTER = 1 & W_WE=1 & WB_A0 = 0 CONSTANT WRITE_LBA_15_0,03 ; STROBE_CF_READER = 1 & W_WE=1 & WB_A0 = 1 CONSTANT WRITE_LBA_27_16,07 ;-- ;-- SLAVE INTERFACE ;-- CONSTANT DATA_WB_OUT_7_0_SLAVE,03 CONSTANT DATA_WB_OUT_15_8_SLAVE,04 CONSTANT CONTROL_WB_OUT_SLAVE,05 ; D7 = D6 = D5 D4 = D3 = ; D2 = TAG1_ERROR ; D1 = TAG0_WORD_AVAILABLE ; D0 = ACK_O_SLAVE CONSTANT ACK_O_SLAVE,01 CONSTANT TAG0_WORD_AVAILABLE,02 CONSTANT ERROR,04 ;-- ;-- BUS CONTROL SIGNALS ;-- CONSTANT CONTROL_OUT_MASTER,06 ; D7 = D6 = D5 = D4 = D3 = D2 = D1 = ; D0 = WB_BUS_MASTER_WRITE_ENABLE CONSTANT WB_BUS_MASTER_WRITE_ENABLE,01 CONSTANT CONTROL_OUT_SLAVE,07 ; D7 = D6 = D5 = D4 = D3 = D2 = D1 = ; D0 = WB_BUS_SLAVE_WRITE_ENABLE CONSTANT WB_BUS_SLAVE_WRITE_ENABLE,01 ;-- ;-- EXTERNAL REGISTERS FOR MORE DATA ALLOCATION (OTHER OPTION IS THE USE OF ;-- ANOTHER BLOCK RAM IF IT IS AVALIABLE ;-- CONSTANT TMP_OUT_0,08 CONSTANT TMP_OUT_1,09 CONSTANT TMP_OUT_2,0A CONSTANT TMP_OUT_3,0B CONSTANT TMP_OUT_4,0C CONSTANT TMP_OUT_5,0D CONSTANT TMP_OUT_6,0E CONSTANT TMP_OUT_7,0F ;-- ;-- INPUT PORTS ;-- ;-- ;-- WISHBONE INTERFACE PORTS - INPUTS ;-- CONSTANT CONTROL_WB_IN_MASTER,00 ; D7 = D6 = D5 = D4 = D3 = D2 = ; D1 = ERROR_INPUT ; D0 = ACK_I_MASTER ; CONSTANT ACK_I_MASTER,01 CONSTANT ERROR_INPUT,02 CONSTANT CONTROL_WB_IN_SLAVE,01 ; D7 = D6 = D5 = D4 = D3 = D2 = ; D1 = - ; D0 = STB_I_SLAVE ; CONSTANT STB_I_SLAVE,01 ;CONSTANT TAG0_FORCE_RESET,02 ;-- ;-- WISHBONE INTERFACE PORTS - INPUTS ;-- CONSTANT DATA_WB_IN_7_0_MASTER,02 CONSTANT DATA_WB_IN_15_8_MASTER,03 ;-- ;-- EXTERNAL REGISTERS FOR MORE DATA ALLOCATION (OTHER OPTION IS THE USE OF ;-- ANOTHER BLOCK RAM IF IT IS AVALIABLE ;-- CONSTANT TMP_IN_0,04 CONSTANT TMP_IN_1,05 CONSTANT TMP_IN_2,06 CONSTANT TMP_IN_3,07 CONSTANT TMP_IN_4,08 CONSTANT TMP_IN_5,09 CONSTANT TMP_IN_6,0A CONSTANT TMP_IN_7,0B ;-- ;-- REGISTERS INITIALIZATION ;-- inicialization: ; ; WISHBONE INTERFACES INIZIALIZATION ; LOAD sF,00 OUTPUT sF,DATA_WB_OUT_7_0_MASTER OUTPUT sF,DATA_WB_OUT_15_8_MASTER OUTPUT sF,DATA_WB_OUT_7_0_SLAVE OUTPUT sF,DATA_WB_OUT_15_8_SLAVE OUTPUT sF,CONTROL_WB_OUT_MASTER OUTPUT sF,CONTROL_WB_OUT_SLAVE ; ; WAIT FOR 410NS*3 (RESET DELAY) main: ; PROCESS MASTER BOOT RECORD CALL process_master_boot_record ; PROCESS ROOT DIRECTORY CALL process_root_directory start: CALL cluster_2_lba ;CALL write_lba_to_slave ; sector_per_cluster -> sector_per_cluster_readed LOAD s4,s7 ; 256 -> (s6) SECTOR_WORDS_READED CALL read_sector idle: INPUT s6,CONTROL_WB_IN_SLAVE ; CHECK STB INPUT ; CONTROL_WB_IN_SLAVE-> TMP (s6) ; IF STB=1 GO TO THE NEXT STATE ; IF STB=0 GO TO THE IDLE STATE AND s6,STB_I_SLAVE JUMP Z,idle transfer_word_to_master: CALL read_word_from_slave CALL write_a_word_to_master ; (SECTOR WORDS READED)-1 SUB s5,01 check_sectors_words_readed: ; IF sector_words_readed = 0 THEN READ_NEW_SECTOR ; IF sector_words_readed > 0 THEN TRANSFER_WORD_TO_MASTER AND s5,s5 CALL Z,check_sector_per_cluster_readed JUMP idle track_new_cluster: ; save the number of dummy reads that must be done when the fat sector will be readed ; an are stored into s5 register ; in s0 bits 6-0 of the cluster number (offset in the sector -> 256 words-fat16 entries) ; as is each read operation a word is readed no multiplication is needed ; RESTORE CLUSTER NUMBER INPUT s0,TMP_IN_4 INPUT s1,TMP_IN_5 INPUT s2,TMP_IN_6 INPUT s3,TMP_IN_7 ; ; compose LBA address of the sector of the fat that must be readed ; ; SHIFT RIGHT 15-8 TO 7-0 ; LOAD sF,07 do_shift: SR0 s3 ; uses the carry for the MSB and stores LSB into the carry SRA s2 SRA s1 SRA s0 SUB sF,01 JUMP NZ,do_shift CALL add_load_fat_begin_lba ; adds fat_begin_lba to the sector relative to the fat obteined from the cluster ; now there is the lba of the FAT sector that must be readed in s0,s1,s2,s3 CALL write_lba_to_slave ; -- DUMMY READ OF THE WORDS OF THE SECTOR TILL THE ONE OF THE CLUSTER INTEGER INPUT sF,TMP_IN_4 AND sF,7F CALL do_dummy_reads_from_slave ; ; (sD) data[7:0] WB MASTER -> (s0) TEMPORAL REGISTER ; (sE) data[7:0] WB MASTER -> (s1) TEMPORAL REGISTER ; READ 2 BYTES CALL read_word_from_slave LOAD s0,sD LOAD s1,sE ; (sD) data[7:0] WB MASTER -> (s2) TEMPORAL REGISTER ; (sE) data[7:0] WB MASTER -> (s3) TEMPORAL REGISTER ; READ 2 BYTES ; ; CHECK IF ITS THE LAST ONE ; CB3-CL2-CB1-CB0 IN FAT LITTLE ENDIAN ORDER CB0-CB1 CB2-CB3 LOAD sF,sE SUB sF,FF JUMP NZ,continue_file_processing LOAD sF,sD SUB sF,FF JUMP NZ,continue_file_processing file_end: ; infinite loop (file readed and tranferred) JUMP file_end continue_file_processing: ; in s0,s1 is the cluster name ; -- ; (SECTOR WORDS READED)= 256 ; sector_per_cluster -> sector_per_cluster_readed LOAD s2,00 LOAD s3,00 LOAD s4,s7 CALL cluster_2_lba CALL read_sector RETURN add_load_fat_begin_lba: INPUT sF,TMP_IN_0 ADD s0,sF INPUT sF,TMP_IN_1 ADDCY s1,sF INPUT sF,TMP_IN_2 ADDCY s2,sF INPUT sF,TMP_IN_3 ADDCY s3,sF RETURN check_sector_per_cluster_readed: ; IF sector_per_cluster_readed = 0 THEN TRACK_NEW_CLUSTER ; IF sector_per_cluster_readed > 0 THEN CHECK SECTOR WORDS READED ; (sector_per_cluster_readed)-1 ; (SECTOR WORDS READED)= 256 SUB s4,01 AND s4,s4 JUMP Z,track_new_cluster read_new_sector: ; (SECTOR WORDS READED)= 256 ; increment LBA ; sector_per_cluster -> sector_per_cluster_readed-1 ADD s0,01 ADDCY s1,00 ADDCY s2,00 ADDCY s3,00 read_sector: LOAD s5,00 CALL write_lba_to_slave RETURN ; ; -- ; -- PROCESS MASTER BOOT RECORD (READ LBA BEGIN OF THE FIRST PARTITION) ; -- process_master_boot_record: ; ; LOAD LBA FOR MBR READ ; LOAD s0,00 LOAD s1,00 LOAD s2,00 LOAD s3,00 CALL write_lba_to_slave ; information of the lba begin for the first partition ; has an offset of 454 bytes -> 227(0xE3) words LOAD sF,E3 CALL do_dummy_reads_from_slave ; ; -- ; -- MBR READ - Partition_LBA_Begin EXTRACTION ; -- ; ; (sD) data[7:0] WB MASTER -> (s0) lba ; (sE) data[15:8] WB MASTER -> (s1) lba ; (sD) data[7:0] WB MASTER -> (s2) lba ; (sE) data[15:8] WB MASTER -> (s3) lba call store_all_temporal_registers LOAD s8,s0 LOAD s9,s1 LOAD sA,s2 LOAD sB,s3 ; ; NOW IS THE LBA_BEGIN ON THE TMP REGISTERS ; -------------------- ; READ FIRST SECTOR (FAT32 VOLUMEN ID) OF THE PARTITION ; --------------------- CALL write_lba_to_slave ; ; READ -> SECTORS_PER_CLUSTER (OFFSET 0x0D) ; ; offset 0x0D (13) => READ 13 bytes -> 6(0x06) words and drop LSB in the next LOAD sF,06 CALL do_dummy_reads_from_slave ; ; (sE) data[7:0] WB MASTER -> (s7) SECTORS PER CLUSTER CALL read_word_from_slave LOAD s7,sE ; ; READ -> Number_of_Reserved_Sectors (2 bytes) (OFFSET 0x0E) ; ; offset 0x0E (14) => READ 2 bytes -> 1(0x01) words ; (sD) data[15:8] WB MASTER -> (s6) TEMPORAL REGISTER CALL read_word_from_slave LOAD s6,sD ; (sE) data[7:0] WB MASTER -> (s4) TEMPORAL REGISTER ; LOAD s4,sE ; ;fat_begin_lba = Partition_LBA_Begin + Number_of_Reserved_Sectors ; ADD s8,s6 ADDCY s9,s4 ADDCY sA,00 ADDCY sB,00 ; store fat_begin_lba in external registers OUTPUT s8,TMP_OUT_0 OUTPUT s9,TMP_OUT_1 OUTPUT sA,TMP_OUT_2 OUTPUT sB,TMP_OUT_3 ; ;cluster_begin_lba = Partition_LBA_Begin + Number_of_Reserved_Sectors + ; (Number_of_FATs * Sectors_Per_FAT)+ RootDirSectors; ;cluster_begin_lba = fat_begin_lba + (Number_of_FATs * Sectors_Per_FAT)+ RootDirSectors; ; READ -> Number_of_Fats (OFFSET 0x10) (always 2) ; ; offset 0x10 (16) => READ 2 bytes -> 1(0x01) words ; ; (sD) data[7:0] WB MASTER -> (s6) TEMPORAL REGISTER CALL read_word_from_slave LOAD s6,sD ; ; FOR FAT16 => NUMBER OF SECTORS OCCUPIED BY THE ROOT DIRECTORY (BYTES_PER_SEC=512) ; ; READ -> RootEntCnt (OFFSET 0x11) (FAT16 PROCESSING) ; RootDirSectors=((BPB_RootEntCnt*32)+(BPB_BytesPerSec-1))/BPB_BytesPerSec ; offset 0x11 (17) => READ 1 bytes ; ; (sE) data[7:0] WB MASTER -> (s0) TEMPORAL REGISTER LOAD s0,sE ; (sD) data[15:0] WB MASTER -> (sD) TEMPORAL REGISTER - offset 0x12 (18) => READ 1 bytes CALL read_word_from_slave LOAD s1,sD ; MULTIPLY BY 32 (100000) 5 SHIFTS TO THE LEFT LOAD sF,05 ; LSB '0' mult_32: SL0 s0 ; CARRY -> LSB , MSB -> CARRY SLA s1 SUB sF,01 JUMP NZ,mult_32 ;BPB_RootEntCnt*32+(BPB_BytesPerSec-1) 511 (0x1FF) ;ADD s0,FF (if rounds up => not necessary??) ;ADDCY s1,01 ;/BPB_BytesPerSec (512) (1000000000)9 SHIFTS TO THE RIGHT LOAD sF,09 div_512: ; uses the carry for the MSB and stores LSB into the carry SR0 s1 SRA s0 SUB sF,01 JUMP NZ,div_512 ; ROUNDs UP ;ADD s0,01 ;ADDCY s1,00 ;fat_begin_lba + RootDirSectors ADD s8,s0 ADDCY s9,s1 ADDCY sA,s2 ADDCY sB,s3 ; READ -> Sectors_per_fat (OFFSET 0x24) ; ; offset 0x16 (22) => READ 2 bytes -> 01(0x01) words ; LOAD sF,01 CALL do_dummy_reads_from_slave CALL store_all_temporal_registers ; (Number_of_FATs * Sectors_Per_FAT) ; Number_of_FATs = 2 (10) . Do a shift to the left of the Sectors_Per_Fat ; *** FAT16 = Sectors_per_fat(BPB_FATSz16) ; LSB '0' SL0 s0 ; CARRY -> LSB , MSB -> CARRY SLA s1 ;SLA s2 for fat16 only 2 bytes ;SLA s3 ; fat_begin_lba + RootDirSectors + (Number_of_FATs * Sectors_Per_FAT) ADD s8,s0 ADDCY s9,s1 ADDCY sA,00 ADDCY sB,00 ; cluster_begin_lba is stored in s8, s9, sA, SB ; ; FOR FAT16 ROOT DIRECTORY POSITION IS FIXED ; root_first_lba = fat_begin_lba(in external regs) + (Number_of_FATs * Sectors_Per_FAT) (s0,s1,s2,s3) ; LOAD s2,00 LOAD s3,00 CALL add_load_fat_begin_lba ; s0,s1,s2,s3 have Root directory begin lba RETURN store_all_temporal_registers: ; READ 2 BYTES CALL read_word_from_slave ; (sD) data[7:0] WB MASTER -> (s0) TEMPORAL REGISTER ; (sE) data[7:0] WB MASTER -> (s1) TEMPORAL REGISTER LOAD s0,sD LOAD s1,sE ; (sD) data[7:0] WB MASTER -> (s2) TEMPORAL REGISTER ; (sE) data[7:0] WB MASTER -> (s3) TEMPORAL REGISTER ; READ 2 BYTES CALL read_word_from_slave LOAD s2,sD LOAD s3,sE RETURN process_root_directory: ; INPUT : ; s0,s1,s2,s3 root directory lba (FAT16- FIXED) ; CALL cluster_2_lba ; now s0,s1,s2,s3 contains the lba for the root directory ; the first 32 byte record on the sector must be the root directory information ; check if EOF (first byte of the 32 bytes is 0) CALL write_lba_to_slave check_for_a_file: CALL read_word_from_slave ; (sD) data[7:0] WB MASTER -> (s6) TEMPORAL REGISTER LOAD s6,sD LOAD sF,s6 AND sF,sF ; if sF=0 the is not directory => error JUMP Z,put_error_code ; ; check that is not a deleted entry ; ; (sD) data[7:0] WB MASTER -> (s6) TEMPORAL REGISTER LOAD sF,E5 AND sF,s6 ; if s6=E5 is a deteled entry => check for new one (offset => sF) JUMP Z,check_next_directory_entry check_attribute: ; ATTRIBUTE -> OFFSET Bh ; check that is not a directory or LONG NAME ; 00arshdv - DV for long name - D for directory ; (sD) data[7:0] WB MASTER -> (s6) TEMPORAL REGISTER LOAD sF,04 CALL do_dummy_reads_from_slave CALL read_word_from_slave LOAD s6,sE LOAD sF,03 AND sF,s6 JUMP NZ,check_next_directory_entry_attribute ; if s6=0 that is not a file => error ;JUMP Z,check_next_directory_entry ; check that is not a directory ; check that is a file (short filename entry) ; in other case error ; ; ; READ CLUSTER INFORMATION FOR THE FILE ; CALL read_dir_cluster_hi_cluster_low RETURN check_next_directory_entry: ; go fwd 11 words LOAD sF,05 CALL do_dummy_reads_from_slave check_next_directory_entry_attribute: ; go fwd 5 words LOAD sF,0A CALL do_dummy_reads_from_slave JUMP check_for_a_file read_dir_cluster_hi_cluster_low: ; INPUT : ; before arrive here first two bytes of the directory ; structure must be readed ; OUTPUT : ; s0,s1 : CLUS_LOW ; s2,s3 : CLUS_HI ; ; READ -> cluster_HI (OFFSET 0x14) ; ; offset 0x14 (20) => READ 18 bytes -> 9(0x09) words ; LOAD sF,04 CALL do_dummy_reads_from_slave ; (sD) data[7:0] WB MASTER -> s2 ; (sE) data[7:0] WB MASTER -> s3 ; READ 2 BYTES CALL read_word_from_slave LOAD s2,sD LOAD s3,sE OUTPUT sE,TMP_OUT_7 ; ; READ -> cluster_low(OFFSET 0x1A) ; ; offset 0x1A (26) => READ 4 bytes -> 2(0x02) words ; LOAD sF,02 CALL do_dummy_reads_from_slave ; (sD) data[7:0] WB MASTER -> s0 ; (sE) data[7:0] WB MASTER -> s1 ; READ 2 BYTES CALL read_word_from_slave LOAD s0,sD LOAD s1,sE ; s0,s1 clus_low s3,s4 - clus_high RETURN ; -- MBR READ OPERATION - LBA BEGIN DETERMINATION ; '00' -> LBA_7_0,LBA_15_8,LBA_23_16,LD_LBA_27_24 cluster_2_lba: ; -- ; -- LBA ADDRESS DETERMINATION ; -- ; lba_addr = cluster_begin_lba + (cluster_number - 2) * sectors_per_cluster; ; ; INPUT : ; s0 : CLUSTER_NUMBER0, s1 : CLUSTER_NUMBER1, s2: CLUSTER_NUMBER2, s3 : CLUSTER_NUMBER3 ; OUTPUT : ; s0 : LBA_ADDR_7_0 TMP1, s1 : LBA_ADDR_15_8, s2 : LBA_ADDR_24_16, s3 : LBA_ADDR_27_24 ; ; cluster_number - 2 ; OUTPUT s0,TMP_OUT_4 OUTPUT s1,TMP_OUT_5 OUTPUT s2,TMP_OUT_6 OUTPUT s3,TMP_OUT_7 SUB s0,02 SUBCY s1,00 SUBCY s2,00 SUBCY s3,00 ; ; (cluster_number - 2) * sectors_per_cluster(s7); ; ; to perform the multiplication as sector_per_cluster is 2 multiple must be known ; who many times must be shifted ; (use sD as temporal register) LOAD sF,08 LOAD sD,s7 multiply: SR0 sD ; loop until detection of the 1 (2 multiple) - Add timeout!!! JUMP C,add_cluster_begin_lba ; LSB '0' SL0 s0 ; CARRY -> LSB , MSB -> CARRY SLA s1 SLA s2 SLA s3 JUMP multiply add_cluster_begin_lba: ; lba_addr (TMP0,TMP1,TMP2,TMP3)= cluster_begin_lba + (cluster_number - 2) * sectors_per_cluster; ADD s0,s8 ADDCY s1,s9 ADDCY s2,sA ADDCY s3,sB RETURN ; -- ; -- WRITE A WORD INTO THE WB SLAVE INTERFACE (TO THE MASTER) ; -- ; INPUTS : ; TMP0 : LSB TO DATA_WB_OUT_7_0_SLAVE ; TMP1 : MSB TO DATA_WB_OUT_15_8_SLAVE ; write_a_word_to_master: ; TMP0 => DATA_WB_OUT_7_0_SLAVE OUTPUT sD,DATA_WB_OUT_7_0_SLAVE ; 00 => DATA_WB_OUT_15_8_SLAVE ;LOAD sF,00 -- 8 BIT VERSION ;OUTPUT sF,DATA_WB_OUT_15_8_SLAVE -- 8 BIT VERSION OUTPUT sE,DATA_WB_OUT_15_8_SLAVE CALL write_a_byte_to_master ; ; CHECK STB INPUT | CONTROL_WB_IN_SLAVE-> TMP (s6) ; wait_strobe: INPUT s6,CONTROL_WB_IN_SLAVE ; ; AND s6,STB_I_SLAVE JUMP Z,wait_strobe ; TMP1 => DATA_WB_OUT_7_0_SLAVE ; OUTPUT sE,DATA_WB_OUT_7_0_SLAVE ; 00 =>DATA_WB_OUT_15_8_SLAVE ;LOAD sF,00 -- 8 BIT VERSION ;OUTPUT sF,DATA_WB_OUT_15_8_SLAVE -- 8 BIT VERSION ;CALL write_a_byte_to_master -- 8 BIT VERSION RETURN write_a_byte_to_master: ; ; WB SLAVE WRITE ENABLE ACTIVE ; LOAD sF,WB_BUS_SLAVE_WRITE_ENABLE OUTPUT sF,CONTROL_OUT_SLAVE ; ; ACK TO THE MASTER UNTIL STB FINISH ; ack_to_the_master: LOAD sF,ACK_O_SLAVE OUTPUT sF,CONTROL_WB_OUT_SLAVE ; ; LOAD sF,00 OUTPUT sF,CONTROL_OUT_SLAVE OUTPUT sF,CONTROL_WB_OUT_SLAVE RETURN ; -- ; -- WRITE A LBA INTO THE WB MASTER INTERFACE (TO THE SLAVE) ; -- ; INPUTS : ; TMP0 : LBA_ADDR_7_0, TMP1 : LBA_ADDR_15_8, TMP2 : LBA_ADDR_24_16, TMP3 : LBA_ADDR_27_24 ; ; write_lba_to_slave: ; ; WB MASTER WRITE ENABLE ACTIVE ; LOAD sF,WB_BUS_MASTER_WRITE_ENABLE OUTPUT sF,CONTROL_OUT_MASTER ;write_lba_15_0_to_slave: ; ; TMP0 : LBA_ADDR_7_0 (s0) => DATA_WB_OUT_7_0_MASTER ; TMP1 : LBA_ADDR_15_8 (s1) => DATA_WB_OUT_15_8_MASTER ; OUTPUT s0,DATA_WB_OUT_7_0_MASTER OUTPUT s1,DATA_WB_OUT_15_8_MASTER ; ; -- ; -- WRITE LBA 15-0 TO THE SLAVE ; -- ; ; WB_CONTROL_OUT_MASTER ; W_WE_MASTER = 1 ; STB_O_MASTER = 1 ; A0 = 0 ; LOAD sF,WRITE_LBA_15_0 OUTPUT sF,CONTROL_WB_OUT_MASTER ; ; WAIT FOR THE ACK ; CALL wait_for_the_ack ;write_lba_27_16_to_slave: ; ; TMP2 : LBA_ADDR_23_16 (s2) => DATA_WB_OUT_7_0_MASTER ; TMP3 : LBA_ADDR_27_24 (s3) => DATA_WB_OUT_15_8_MASTER ; OUTPUT s2,DATA_WB_OUT_7_0_MASTER OUTPUT s3,DATA_WB_OUT_15_8_MASTER ; -- ; -- WRITE LBA 27-16 TO THE SLAVE ; -- ; WB_CONTROL_OUT_MASTER ; W_WE_MASTER = 1 ; STB_O_MASTER = 1 ; A0 = 0 ; LOAD sF,WRITE_LBA_27_16 OUTPUT sF,CONTROL_WB_OUT_MASTER ; ; WAIT FOR THE ACK ; CALL wait_for_the_ack ; -- ; -- FINISH WRITE OPERATION ON THE MASTER WB INTERFACE ; -- ; ; WB_CONTROL_OUT_MASTER ; W_WE_MASTER = 0 ; STB_O_MASTER = 0 ; A0 = 0 ; LOAD sF,00 OUTPUT sF,CONTROL_WB_OUT_MASTER OUTPUT sF,CONTROL_OUT_MASTER RETURN ; -- ; -- PERFORM DUMMY READS FROM THE WB SLAVE ; -- ; -- IN sF ARE THE NUMBER OF WORDS THAT MUST BE READED ; -- do_dummy_reads_from_slave: LOAD s6,sF dummy_reads_from_slave: CALL read_word_from_slave SUB s6,01 JUMP NZ,dummy_reads_from_slave RETURN ; -- ; -- PERFORM A WORD READING FROM THE WB SLAVE ; -- read_word_from_slave: ; WB_CONTROL_OUT_MASTER ; W_WE_MASTER = 0 ; STB_O_MASTER = 1 ; A0 = 0 ; wait state LOAD sF,READ_SLAVE OUTPUT sF,CONTROL_WB_OUT_MASTER ; ; WAIT FOR THE ACK ; ; CALL wait_for_the_ack ;JUMP Z,data_available_on_wb_master wait_for_the_ack: ; ; CONTROL_WB_IN_MASTER -> TMP (s6) ; INPUT sF,CONTROL_WB_IN_MASTER ; AND sF,ACK_I_MASTER JUMP Z,wait_for_the_ack data_available_on_wb_master: ; This part is not necessary in write operations ; DATA_WB_IN_7_0_MASTER -> (sD) data[7:0] WB MASTER ; DATA_WB_IN_15_8_MASTER -> (sE) data[15:8] WB MASTER INPUT sD,DATA_WB_IN_7_0_MASTER INPUT sE,DATA_WB_IN_15_8_MASTER ; DISABLE RD/WR OPERATION REQUEST LOAD sF,00 OUTPUT sF,CONTROL_WB_OUT_MASTER RETURN put_error_code: LOAD sF,ERROR OUTPUT sF,CONTROL_WB_OUT_SLAVE JUMP put_error_code interrupt: RETURNI ENABLE @ 1.1.1.1 log @no message @ text @@ 1.1.1.2 log @check 1640 @ text @d2 1 a2 1 ; APERT - UPV/EHU 2003 - DISTRIBUTED UNDER GPL LICENSE d96 1 a96 1 initialization: d98 1 a98 1 ; WISHBONE INTERFACES INITIALIZATION @