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SPI Flash Programming in P2ASM — Parallax Forums

SPI Flash Programming in P2ASM

proppyproppy Posts: 37
edited 2025-07-12 03:16 in Propeller 2

Hello!

I been working with SPI code a bit and the onboard SPI flash for the P2 Edge. I stumbled upon this code for an SPI programming but ran it through FlexProp and got an error for this line:
https://forums.parallax.com/discussion/165060/spi-flash-programmer-code/p1

testin  #spi_do     wc

to this

testp   #spi_do     wc

However, it doesn't seem to blink anything. I was able to try some of the code for reading and changed a few things. When I Compile and Flash a program via FlexProp the program is stored. I can then read/run the program on flash. Not sure why the code in the thread does not seem to work for the writing though.

Comments

  • RaymanRayman Posts: 15,358

    testp looks right. Not sure why doesn't work... Maybe post full code?

  • RaymanRayman Posts: 15,358

    You can get the spreadsheet with all the P2 assembly instructions here:
    https://www.parallax.com/propeller-2/documentation/

  • proppyproppy Posts: 37

    Hey there @Rayman!

    Sure thing! Here is that complete code:

    ' Program SPI flash with signed OUTB blinker program
' - Connect SPI flash (M25P80 okay) with pull-ups on spi_cs and spi_ck
' - Blinks OUTB on boot-up

CON

  spi_cs = 61
  spi_ck = 60
  spi_di = 59
  spi_do = 58

DAT


        org
'
'
' Init SPI pins
'
        outh    #spi_cs

        dirh    #spi_cs
        dirh    #spi_ck
        dirh    #spi_di
'
'
' Erase 1st $1000 bytes
'
        call    #spi_wrena      'write enable

        mov cmd,cmd_erase       'sector erase
        call    #spi_cmd32

        call    #spi_wait       'wait for completion
'
'
' Program first $400 bytes
'
        loc ptra,#\pgmdata      'point to program data

.program    call    #spi_wrena      'write enable

        mov cmd,cmd_program     'page program
        or  cmd,adr
        call    #spi_cmd32

.byte       rdbyte  cmd,ptra++      'get byte

        mov x,#8            'send byte
        shl cmd,#24
        call    #spi_out

        add adr,#1          'page done?
        test    adr,#$FF    wz
    if_nz   jmp #.byte

        call    #spi_wait       'wait for completion

        testb   adr,#10     wz  'another page?
    if_z    jmp #.program
'
'
' Read data back to outa for viewing on logic analyzer
'
        mov dira,#$1FF

.read1k     mov cmd,cmd_read        'start read
        call    #spi_cmd32

        outh    #8          'trigger signal
        outl    #8

        decod   y,#10           'read byte to outa
.read       call    #spi_in
        setbyte outa,cmd,#0
        djnz    y,#.read

        jmp #.read1k        'loop
'
'
' SPI write enable
'
spi_wrena   mov cmd,#$06        'write enable
        call    #spi_cmd8

        ret
'
'
' SPI wait while busy
'
spi_wait    mov cmd,#$05
        call    #spi_cmd8

.wait       call    #spi_in
        test    cmd,#$01    wc
    if_c    jmp #.wait

        ret
'
'
' SPI command
'
spi_cmd32   mov x,#32
        jmp #spi_cmd

spi_cmd8    mov x,#8
        shl cmd,#24

spi_cmd     outh    #spi_cs
        outl    #spi_cs
'
'
' SPI long/byte out (x=bits, cmd=msbdata)
'
spi_out     rep @.r,x
        shl cmd,#1      wc
        outc    #spi_di
        outh    #spi_ck
        outl    #spi_ck
.r
        ret
'
'
' SPI byte in (cmd)
'
spi_in
    mov y, #8
    mov cmd, #0
.rdloop
    outh    #spi_ck
    testp   #spi_do wc
    rcl cmd, #1
    outl    #spi_ck
    djnz    y, #.rdloop
    ret
'
'
' Data
'
cmd_erase   long    $20_00_00_00
cmd_program long    $02_00_00_00
cmd_read    long    $03_00_00_00
adr     long    0
'
'
' Variables
'
cmd     res 1
x       res 1
y       res 1
'
'
' Program Data
'
' first 20 bytes are blinker program:
'
'   not dirb
'.lp    not outb
'   waitx   ##20_000_000/4
'   jmp #.lp
'
' last 32 bytes are signature (key=0)
'
    orgh

pgmdata byte    $FB,$F7,$23,$F6,$FD,$FB,$23,$F6,$25,$26,$80,$FF,$28,$80,$66,$FD 'blinker program
    byte    $F0,$FF,$9F,$FD,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00,$00
    byte    $99,$AA,$44,$98,$86,$E2,$C8,$71,$C3,$1E,$60,$BF,$A3,$36,$19,$7A 'SHA-256/HMAC signature
    byte    $F5,$3D,$53,$97,$5C,$AF,$BA,$BB,$B7,$7F,$C3,$0A,$B4,$24,$02,$40

    I only changed that line in FlexProp. But even then it doesn't work as it should i think. I know it's writing something though since it overwrote the program i had in place previously on the spi Flash. I've been having a bit of trouble with this thing having the boot mode on/off. Very weird behavior at times. I got the read working from using the manual a bit and this code.

  • JonnyMacJonnyMac Posts: 9,375
    edited 2025-06-19 23:04

    Yes, testp is the correct instruction. This code is for PNut (FlexProp does inline assembly differently), but this code does work.

    pri shiftin(bits) : result | tix

  tix := ticks                                                  ' tix in 1/2 clock

  org
                rep       #6, bits
                 testp    #SF_MISO                      wc      ' scan MISO
                 rcl      result, #1                            ' move new bit to result.0
                 drvh     #SF_SCLK                              ' clock next bit
                 waitx    tix
                 drvl     #SF_SCLK
                 waitx    tix
  end
  • proppyproppy Posts: 37

    Hello @JonnyMac!

    @JonnyMac said:
    Yes, testp is the correct instruction. This code is for PNut (FlexProp does inline assembly differently), but this code does work.

    Thank you. Okay I did get reading working in another program. I think i'll pick apart the writing part a bit under FlexProp and see what I come up with.

  • evanhevanh Posts: 16,582

    I recommend use of SPI clock mode 3 rather than 0. The shared SD card wiring conflicts much less when the clock idles high.

  • proppyproppy Posts: 37

    Howdy @evanh

    @evanh said:
    I recommend use of SPI clock mode 3 rather than 0. The shared SD card wiring conflicts much less when the clock idles high.

    I'll give this a shot as well in the future. Would this wiring conflict cause an SD card to randomly delete itself? I went through some SD card code and created a driver for writing which works based on the reading you had helped with before. I noticed if I ran the code a few times though it blew away the SD card once i tried to read. Off-topic but just curious.

  • evanhevanh Posts: 16,582
    edited 2025-06-20 13:53

    All it would take is the erasure of block zero to stop a SD card from mounting correctly. So, yes, routines built to write blocks can easily accidentally make the card look empty. There is no filesystem management by the card itself.

    As for SPI clock mode 0, I expect it would more likely cause lock-ups rather than erasures. But I have no specific evidence of what actually happens though.

  • evanhevanh Posts: 16,582

    Another problem I discovered recently is the historical FSRW SD card FAT filesystem for the Propellers has had deficiencies in its driver layer that did not wait for card busy condition. This is particularly bad thing when writing blocks. The chances of skipped blocks is high.

    If you've been using FSRW software then that would explain filesystem corruption.

  • Wuerfel_21Wuerfel_21 Posts: 5,405

    Well, the CRC checksums are supposed to protect against such corruption, but SPI mode doesn't use them by default... On the P2 nothing should be stopping us from using CMD59 to enable them.

  • proppyproppy Posts: 37
    edited 2025-06-20 20:05

    @evanh said:
    Another problem I discovered recently is the historical FSRW SD card FAT filesystem for the Propellers has had deficiencies in its driver layer that did not wait for card busy condition. This is particularly bad thing when writing blocks. The chances of skipped blocks is high.

    If you've been using FSRW software then that would explain filesystem corruption.

    Thanks for this. That narrows things down a bit. I'm doing FAT32 cause that's what I'm most familiar with.

    I got a little further but I'm pretty sure the program never moves from hub ram to the flash.

    ' Program SPI flash with signed program

CON

  spi_cs = 61
  spi_ck = 60
  spi_di = 59
  spi_do = 58

DAT
    orgh

pgmdata byte $02, $00, $00, $FF, $04, $00, $6C, $FC, $02, $00, $00, $FF, $48, $84, $4C, $FC
byte $02, $00, $00, $FF, $49, $00, $4C, $FC, $02, $00, $00, $FF, $04, $02, $6C, $FC
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00, $00
byte $99, $AA, $44, $98, $86, $E2, $C8, $71, $C3, $1E, $60, $BF, $A3, $36, $19, $7A  'SHA-256/HMAC signature
byte $F5, $3D, $53, $97, $5C, $AF, $BA, $BB, $B7, $7F, $C3, $0A, $B4, $24, $02, $40

        org
        asmclk
'
'
' Init SPI pins
'
        outh    #spi_cs
        dirh    #spi_cs
        dirh    #spi_ck
        dirh    #spi_di
'
'
' Erase 1st $1000 bytes
'
        call    #spi_wrena      'write enable

        mov cmd,cmd_erase       'sector erase
        call    #spi_cmd32

        call    #spi_wait       'wait for completion
'
'
' Program first $400 bytes
'
        loc ptra,#\pgmdata      'point to program data

.program    call    #spi_wrena      'write enable

        mov cmd,cmd_program     'page program
        or  cmd,adr
        call    #spi_cmd32

.byte       rdbyte  cmd,ptra++      'get byte

        mov x,#8            'send byte
        shl cmd,#24
        call    #spi_out

        add adr,#1          'page done?
        test    adr,#$FF    wz
    if_nz   jmp #.byte

        call    #spi_wait       'wait for completion

        cmp adr, ##$100 wz
        if_nz jmp #.program

'
'
' Read data back to outa for viewing on logic analyzer
'
        mov dira,#$1FF

.read1k     mov cmd,cmd_read        'start read
        call    #spi_cmd32

        outh    #8          'trigger signal
        outl    #8

        decod   y,#10           'read byte to outa
.read       call    #spi_in
        setbyte outa,cmd,#0
        djnz    y,#.read

        jmp #.read1k        'loop
'
'
' SPI write enable
'
spi_wrena   mov cmd,#$06        'write enable
        call    #spi_cmd8

        ret
'
'
' SPI wait while busy
'
spi_wait    mov cmd,#$05
        call    #spi_cmd8

.wait       call    #spi_in
        test    cmd,#$01    wc
    if_c    jmp #.wait

        ret
'
'
' SPI command
'
spi_cmd32   mov x,#32
        jmp #spi_cmd

spi_cmd8    mov x,#8
        shl cmd,#24

spi_cmd     outh    #spi_cs
        outl    #spi_cs
'
'
' SPI long/byte out (x=bits, cmd=msbdata)
'
spi_out     rep @.r,x
        shl cmd,#1      wc
        outc    #spi_di
        outh    #spi_ck
        outl    #spi_ck
.r
        ret
'
'
' SPI byte in (cmd)
'
spi_in      rep @.r,#8
        outh    #spi_ck
        outl    #spi_ck
        testp   #spi_do     wc  'due to latencies, 'testin' is from 2 clocks before 'outh'
        rcl cmd,#1
.r
        ret
'
'
' Data
'
cmd_erase   long    $20_00_00_00    ' Sector Erase command
cmd_program long    $02_00_00_00    ' Page Program command
cmd_read    long    $03_00_00_00    ' Read Data command
adr         long    $00_00_00_00    ' 24-bit address, MSB aligned

'
'
' Variables
'
cmd     res 1
x       res 1
y       res 1
'
'
' Program Data
'
' first 20 bytes are blinker program:
'
'   not dirb
'.lp    not outb
'   waitx   ##20_000_000/4
'   jmp #.lp
'
' last 32 bytes are signature (key=0)
'

    I may plug away at understanding it a bit more later. Also, I think i might need to generate a new signature. I noticed i was using the one found in the example found here: https://forums.parallax.com/discussion/165060/spi-flash-programmer-code/p1. Though honestly it does work if run from hub ram. I kept in the testp but also replaced the testb with cmp

            cmp adr, ##$100 wz
        if_nz jmp #.program
  • ersmithersmith Posts: 6,184

    There's some sample flash programming code in spin2cpp; for example, in Chip's parallax file system (include/filesys/parallax/flash_fs.spin2) and in the littlefs file system code (include/filesys/littlefs/SpiFlash.spin2).

    If you're trying to learn how to write programs into the flash, the sources for loadp2 or propeller-loader would be useful. On the P2 booting from flash is a two step process: the ROM loads the first 256 bytes (or so, I may be misremembering the size) from flash into RAM, and then runs that. So the first part of the flash must be a small stand-alone program capable of loading the rest of the program into flash. Chip's code for this is the file "flash_stub.spin2" in the loadp2 source code (https://github.com/totalspectrum/loadp2).

  • proppyproppy Posts: 37

    Hiya @ersmith!

    Firstly, thank you for all your efforts on FlexProp.

    @ersmith said:
    If you're trying to learn how to write programs into the flash,

    Yes, exactly. I’ll have a look at this stuff before I continue. I would like to finish this before moving onto dual I/O.

  • pik33pik33 Posts: 2,413

    @evanh said:
    I recommend use of SPI clock mode 3 rather than 0. The shared SD card wiring conflicts much less when the clock idles high.

    +1 to this. Mode 3 or problems with SD cards

  • proppyproppy Posts: 37

    Hey all,

    I was able to work out a few things and got the results i was looking for. I decided to use the Flash 6 Click and connect it to my mikroebus adapter on the P2 Edge breakout board. I started from the ground up and worked my way through the commands. So maybe this might help someone else running into the same problem.

    Reading the JEDEC:

    CON
  _CLKFREQ  = 180_000_000

  ' UART on P62
  RX_PIN = 63
  TX_PIN = 62
  BAUD_RATE = 2000000
  SERIAL_CLOCK = (_CLKFREQ / BAUD_RATE)
  BIT_PERIOD = ((SERIAL_CLOCK << 16) & $FFFFFC00) + (8 - 1)

  ' SPI pins
  spi_cs   = 8
  spi_ck   = 9
  spi_miso = 10
  spi_mosi = 11
  spi_hld  = 4
  spi_wp   = 5

DAT
org 0
asmclk

' ---- UART TX init ----
        wrpin   ##(P_ASYNC_TX | P_OE), #TX_PIN
        wxpin   ##BIT_PERIOD, #TX_PIN
        wypin   #1, #TX_PIN
        dirh    #TX_PIN

' ---- SPI GPIO Init ----
        outh    #spi_cs
        outh    #spi_hld
        outh    #spi_wp

        dirh    #spi_cs
        dirh    #spi_ck
        dirh    #spi_mosi
        dirh    #spi_hld
        dirh    #spi_wp

    outh    #spi_ck    ' Clock starts high

' ---- Read JEDEC ID ----
        call    #spi_jedec

' ---- Print JEDEC Information ----
        mov     result, manufacturer_id
        call    #print_hex_byte
        call    #uart_tx_space

        mov     result, memory_type_id1
        call    #print_hex_byte
        call    #uart_tx_space

        mov     result, capacity
        call    #print_hex_byte
        call    #uart_tx_space

        call    #uart_tx_nl

        jmp     #endprog

' ---- JEDEC ID/Information Read ----
spi_jedec
        outl    #spi_cs          ' CS low

        mov     cmd, #$9F
        call    #spi_cmd8        

        call    #spi_in
        mov     manufacturer_id, cmd

        call    #spi_in
        mov     memory_type_id1, cmd

        call    #spi_in
        mov     capacity, cmd

        outh    #spi_cs          ' CS high
        ret

' ---- Send 8 bits (MSB first) ----
spi_cmd8
        mov     x, #8
        shl     cmd, #24
        jmp     #spi_cmd

spi_cmd
        rep     @.r, x
        shl     cmd, #1 wc
        outc    #spi_mosi
        waitx   ##45
        outl    #spi_ck          ' falling edge (sample in slave)
        waitx   ##45
        outh    #spi_ck
.r
        ret

' ---- Read 8 bits (MSB first) ----
spi_in
        mov     y, #8
        mov     cmd, #0
.rdloop
        waitx   ##45
        outl    #spi_ck          ' falling edge: sample MISO
        waitx   ##10             ' setup/hold time
        testp   #spi_miso wc
        rcl     cmd, #1
        waitx   ##45
        outh    #spi_ck
        djnz    y, #.rdloop
        ret

' ---- UART hexadecimal Output ----
print_hex_byte
        mov     temp, result
        mov     pr0, temp
        shr     pr0, #4
        and     pr0, #$F
        call    #print_nibble
        mov     pr0, temp
        and     pr0, #$F
        call    #print_nibble
        ret

print_nibble
        cmp     pr0, #10 wc
  if_b  add     pr0, #"0"
  if_nc add     pr0, #"A"-10
        mov     result, pr0
        call    #uart_tx_char
        ret

' ---- UART character Output ----
uart_tx_char
        wypin   result, #TX_PIN
.tx
        rdpin   pr2, #TX_PIN wc
  if_c  jmp     #.tx
        ret

uart_tx_space
        mov     result, #" "
        call    #uart_tx_char
        ret

uart_tx_nl
        mov     result, #13
        call    #uart_tx_char
        mov     result, #10
        call    #uart_tx_char
        ret

' ---- End ----
endprog

' ---- General Variables ----
cmd     res 1
x       res 1
y       res 1
temp    res 1
result  res 1

' ---- Flash Variables ----
manufacturer_id res 1
memory_type_id1 res 1
capacity res 1

    Performing the write enable

    CON
  _CLKFREQ  = 180_000_000

  ' UART on P62
  RX_PIN = 63
  TX_PIN = 62
  BAUD_RATE = 2000000
  SERIAL_CLOCK = (_CLKFREQ / BAUD_RATE)
  BIT_PERIOD = ((SERIAL_CLOCK << 16) & $FFFFFC00) + (8 - 1)

  ' SPI pins
  spi_cs   = 8
  spi_ck   = 9
  spi_miso = 10
  spi_mosi = 11
  spi_hld  = 4
  spi_wp   = 5

DAT
org 0
asmclk

' ---- UART TX init ----
        wrpin   ##(P_ASYNC_TX | P_OE), #TX_PIN
        wxpin   ##BIT_PERIOD, #TX_PIN
        wypin   #1, #TX_PIN
        dirh    #TX_PIN

' ---- SPI Init ----
        outh    #spi_cs
        outh    #spi_hld
        outh    #spi_wp

        dirh    #spi_cs
        dirh    #spi_ck
        dirh    #spi_mosi
        dirh    #spi_hld
        dirh    #spi_wp

' ----  Write enable ----
        call    #spi_write_enable

' ----  Read Status Register ----
        call #spi_rdsr

' ---- Print Status Register ----
        mov     result, RDSR1
        call    #print_hex_byte
        call    #uart_tx_space

        call    #uart_tx_nl

        jmp     #endprog

' ---- Write Enable ----
spi_write_enable
        outl    #spi_cs          ' CS low

        mov     cmd, #$06
        call    #spi_cmd8        

        outh    #spi_cs          ' CS high
        ret

' ---- READ STATUS REGISTER (RDSR) ----
spi_rdsr
        outl    #spi_cs          ' CS low

        mov     cmd, #$05
        call    #spi_cmd8        

        call    #spi_in
        mov     RDSR1, cmd

        outh    #spi_cs          ' CS high
        ret

' ---- Send 8 bits (MSB first) ----
spi_cmd8
        mov     x, #8
        shl     cmd, #24
        jmp     #spi_cmd

spi_cmd
        rep     @.r, x
        shl     cmd, #1 wc
        outc    #spi_mosi
        waitx   ##45
        outl    #spi_ck          ' falling edge (sample in slave)
        waitx   ##45
        outh    #spi_ck
.r
        ret

' ---- Read 8 bits (MSB first) ----
spi_in
        mov     y, #8
        mov     cmd, #0
.rdloop
        waitx   ##45
        outl    #spi_ck          ' falling edge: sample MISO
        waitx   ##10             ' setup/hold time
        testp   #spi_miso wc
        rcl     cmd, #1
        waitx   ##45
        outh    #spi_ck
        djnz    y, #.rdloop
        ret

' ---- UART hexadecimal Output ----
print_hex_byte
        mov     temp, result
        mov     pr0, temp
        shr     pr0, #4
        and     pr0, #$F
        call    #print_nibble
        mov     pr0, temp
        and     pr0, #$F
        call    #print_nibble
        ret

print_nibble
        cmp     pr0, #10 wc
  if_b  add     pr0, #"0"
  if_nc add     pr0, #"A"-10
        mov     result, pr0
        call    #uart_tx_char
        ret

' ---- UART character Output ----
uart_tx_char
        wypin   result, #TX_PIN
.tx
        rdpin   pr2, #TX_PIN wc
  if_c  jmp     #.tx
        ret

uart_tx_space
        mov     result, #" "
        call    #uart_tx_char
        ret

uart_tx_nl
        mov     result, #13
        call    #uart_tx_char
        mov     result, #10
        call    #uart_tx_char
        ret

' ---- End ----
endprog

' ---- General Variables ----
cmd     res 1
x       res 1
y       res 1
temp    res 1
result  res 1

' ---- Eeprom Variables ----
RDSR1 res 1

    Performing a single byte write, but also the sector erase:

    CON
  _CLKFREQ  = 180_000_000

  ' UART on P62
  RX_PIN = 63
  TX_PIN = 62
  BAUD_RATE = 2000000
  SERIAL_CLOCK = (_CLKFREQ / BAUD_RATE)
  BIT_PERIOD = ((SERIAL_CLOCK << 16) & $FFFFFC00) + (8 - 1)

  ' SPI pins
  spi_cs   = 8
  spi_ck   = 9
  spi_miso = 10
  spi_mosi = 11
  spi_hld  = 4
  spi_wp   = 5

DAT
org 0
asmclk

' ---- UART TX init ----
        wrpin   ##(P_ASYNC_TX | P_OE), #TX_PIN
        wxpin   ##BIT_PERIOD, #TX_PIN
        wypin   #1, #TX_PIN
        dirh    #TX_PIN

' ---- SPI Init ----
        outh    #spi_cs
        outh    #spi_hld
        outh    #spi_wp

        dirh    #spi_cs
        dirh    #spi_ck
        dirh    #spi_mosi
        dirh    #spi_hld
        dirh    #spi_wp

' ----  Write enable ----
        call #spi_write_enable

' ----  Read Status Register ----
        call #spi_rdsr

' ---- Print ----
    mov     addr, #$0         ' Pick address 0x00

        call    #spi_write_enable     ' Send 06h

    call #spi_erase_sector

    call #spi_write_enable

    mov     addr, #$0        ' Pick address 0x00
    mov data, #"A"
    call #spi_byte_write

    mov     result, data
    call    #print_hex_byte
        call    #uart_tx_space

        call    #uart_tx_nl

        jmp     #endprog

' ---- Write Enable ----
spi_write_enable
        outl    #spi_cs          ' CS low

        mov     cmd, #$06
        call    #spi_cmd8        

        outh    #spi_cs          ' CS high
        ret

' ---- READ STATUS REGISTER (RDSR) ----
spi_rdsr
        outl    #spi_cs          ' CS low

        mov     cmd, #$05
        call    #spi_cmd8        

        call    #spi_in
        mov     RDSR1, cmd

        outh    #spi_cs          ' CS high
        ret

spi_erase_sector
        outl    #spi_cs               ' CS low

        mov     cmd, #$20             ' Sector Erase
        call    #spi_cmd8              ' Send command

        call    #spi_send_address24     ' Send address

        outh    #spi_cs        ' CS high

.wait_busy
    call    #spi_rdsr
    testb   RDSR1, #0 wz       ' Test if all bits are 0
  if_z     jmp #.wait_busy    ' Loop again if BUSY/non-ero
  ret                ' Return only when all bits are 0

spi_byte_write      
        outl    #spi_cs          ' CS low

        mov     cmd, #$02          ' WRITE command
        call    #spi_cmd8

        ' Send 24-bit address (A23-A0), top bits don't matter
        mov     cmd, addr
        shr     cmd, #16
        call    #spi_cmd8          ' A23–A16
        mov     cmd, addr
        shr     cmd, #8
        and     cmd, #$FF
        call    #spi_cmd8          ' A15–A8
        mov     cmd, addr
        and     cmd, #$FF
        call    #spi_cmd8          ' A7–A0

        ' Send data byte
        mov     cmd, data
        call    #spi_cmd8

        outh    #spi_cs          ' CS high
        ret

        ' ---- Send 24-bit address ----
spi_send_address24
        mov     cmd, addr
        shr     cmd, #16
        call    #spi_cmd8      ' A23–A16
        mov     cmd, addr
        shr     cmd, #8
        and     cmd, #$FF
        call    #spi_cmd8      ' A15–A8
        mov     cmd, addr
        and     cmd, #$FF
        call    #spi_cmd8      ' A7–A0

        ret


' ---- Send 8 bits (MSB first) ----
spi_cmd8
        mov     x, #8
        shl     cmd, #24
        jmp     #spi_cmd

spi_cmd
        rep     @.r, x
        shl     cmd, #1 wc
        outc    #spi_mosi
        waitx   ##45
        outl    #spi_ck          ' falling edge (sample in slave)
        waitx   ##45
        outh    #spi_ck
.r
        ret

' ---- Read 8 bits (MSB first) ----
spi_in
        mov     y, #8
        mov     cmd, #0
.rdloop
        waitx   ##45
        outl    #spi_ck          ' falling edge: sample MISO
        waitx   ##10             ' setup/hold time
        testp   #spi_miso wc
        rcl     cmd, #1
        waitx   ##45
        outh    #spi_ck
        djnz    y, #.rdloop
        ret

' ---- UART hexadecimal Output ----
print_hex_byte
        mov     temp, result
        mov     pr0, temp
        shr     pr0, #4
        and     pr0, #$F
        call    #print_nibble
        mov     pr0, temp
        and     pr0, #$F
        call    #print_nibble
        ret

print_nibble
        cmp     pr0, #10 wc
  if_b  add     pr0, #"0"
  if_nc add     pr0, #"A"-10
        mov     result, pr0
        call    #uart_tx_char
        ret

' ---- UART character Output ----
uart_tx_char
        wypin   result, #TX_PIN
.tx
        rdpin   pr2, #TX_PIN wc
  if_c  jmp     #.tx
        ret

uart_tx_space
        mov     result, #" "
        call    #uart_tx_char
        ret

uart_tx_nl
        mov     result, #13
        call    #uart_tx_char
        mov     result, #10
        call    #uart_tx_char
        ret

' ---- End ----
endprog

' ---- General Variables ----
cmd     res 1
x       res 1
y       res 1
temp    res 1
result  res 1

' ---- Flash Variables ----
RDSR1 res 1
addr    res 1
data    res 1

    Doing a read of the byte that was written:

    CON
  _CLKFREQ  = 180_000_000

  ' UART on P62
  RX_PIN = 63
  TX_PIN = 62
  BAUD_RATE = 2000000
  SERIAL_CLOCK = (_CLKFREQ / BAUD_RATE)
  BIT_PERIOD = ((SERIAL_CLOCK << 16) & $FFFFFC00) + (8 - 1)

  ' SPI pins
  spi_cs   = 8
  spi_ck   = 9
  spi_miso = 10
  spi_mosi = 11
  spi_hld  = 4
  spi_wp   = 5

DAT
org 0
asmclk

' ---- UART TX init ----
        wrpin   ##(P_ASYNC_TX | P_OE), #TX_PIN
        wxpin   ##BIT_PERIOD, #TX_PIN
        wypin   #1, #TX_PIN
        dirh    #TX_PIN

' ---- SPI Init ----
        outh    #spi_cs
        outh    #spi_hld
        outh    #spi_wp

        dirh    #spi_cs
        dirh    #spi_ck
        dirh    #spi_mosi
        dirh    #spi_hld
        dirh    #spi_wp

' ---- Print ----
    mov     addr, #$0         ' Pick address 0x10
    call #spi_byte_read

    mov     result, data
    call    #print_hex_byte
    call    #uart_tx_space

    mov     result, data
    call #uart_tx_char
        call    #uart_tx_space

        call    #uart_tx_nl

        jmp     #endprog

spi_byte_read       
        outl    #spi_cs

        mov     cmd, #$03          ' READ command
        call    #spi_cmd8

        ' Send 24-bit address
    call #spi_send_address24

        ' Read data byte
        call    #spi_in
        mov     data, cmd          ' Save read byte

        outh    #spi_cs
        ret

spi_send_address24
        mov     cmd, addr
        shr     cmd, #16
        call    #spi_cmd8      ' A23–A16
        mov     cmd, addr
        shr     cmd, #8
        and     cmd, #$FF
        call    #spi_cmd8      ' A15–A8
        mov     cmd, addr
        and     cmd, #$FF
        call    #spi_cmd8      ' A7–A0

        ret

' ---- Send 8 bits (MSB first) ----
spi_cmd8
        mov     x, #8
        shl     cmd, #24
        jmp     #spi_cmd

spi_cmd
        rep     @.r, x
        shl     cmd, #1 wc
        outc    #spi_mosi
        waitx   ##45
        outl    #spi_ck          ' falling edge (sample in slave)
        waitx   ##45
        outh    #spi_ck
.r
        ret

' ---- Read 8 bits (MSB first) ----
spi_in
        mov     y, #8
        mov     cmd, #0
.rdloop
        waitx   ##45
        outl    #spi_ck          ' falling edge: sample MISO
        waitx   ##10             ' setup/hold time
        testp   #spi_miso wc
        rcl     cmd, #1
        waitx   ##45
        outh    #spi_ck
        djnz    y, #.rdloop
        ret

' ---- UART hexadecimal Output ----
print_hex_byte
        mov     temp, result
        mov     pr0, temp
        shr     pr0, #4
        and     pr0, #$F
        call    #print_nibble
        mov     pr0, temp
        and     pr0, #$F
        call    #print_nibble
        ret

print_nibble
        cmp     pr0, #10 wc
  if_b  add     pr0, #"0"
  if_nc add     pr0, #"A"-10
        mov     result, pr0
        call    #uart_tx_char
        ret

' ---- UART decimal Output ----
uart_tx_char
        wypin   result, #TX_PIN
.tx
        rdpin   pr2, #TX_PIN wc
  if_c  jmp     #.tx
        ret

uart_tx_space
        mov     result, #" "
        call    #uart_tx_char
        ret

uart_tx_nl
        mov     result, #13
        call    #uart_tx_char
        mov     result, #10
        call    #uart_tx_char
        ret

' ---- End ----
endprog

' ---- General Variables ----
cmd     res 1
x       res 1
y       res 1
temp    res 1
result  res 1

' ---- Flash Variables ----
RDSR1 res 1
addr    res 1
data    res 1

    Reading again, but for a full page (256 bytes):

    CON
  _CLKFREQ  = 180_000_000

  ' UART on P62
  RX_PIN = 63
  TX_PIN = 62
  BAUD_RATE = 2000000
  SERIAL_CLOCK = (_CLKFREQ / BAUD_RATE)
  BIT_PERIOD = ((SERIAL_CLOCK << 16) & $FFFFFC00) + (8 - 1)

  ' SPI pins
  spi_cs   = 8
  spi_ck   = 9
  spi_miso = 10
  spi_mosi = 11
  spi_hld  = 4
  spi_wp   = 5

DAT
org 0
asmclk

' ---- UART TX init ----
        wrpin   ##(P_ASYNC_TX | P_OE), #TX_PIN
        wxpin   ##BIT_PERIOD, #TX_PIN
        wypin   #1, #TX_PIN
        dirh    #TX_PIN

' ---- SPI Init ----
        outh    #spi_cs
        outh    #spi_hld
        outh    #spi_wp

        dirh    #spi_cs
        dirh    #spi_ck
        dirh    #spi_mosi
        dirh    #spi_hld
        dirh    #spi_wp

' ---- Print ----
    mov     addr, #$0         ' Pick address 0x00
    mov cnt, #0

    call #spi_page_read

        call    #uart_tx_nl

        jmp     #endprog

spi_page_read
        outl    #spi_cs

        mov     cmd, #$03            ' READ command
        call    #spi_cmd8

        ' Send 24-bit address
        mov     cmd, addr
        shr     cmd, #16
        call    #spi_cmd8            ' A23–A16
        mov     cmd, addr
        shr     cmd, #8
        and     cmd, #$FF
        call    #spi_cmd8            ' A15–A8
        mov     cmd, addr
        and     cmd, #$FF
        call    #spi_cmd8            ' A7–A0

        ' Read 256 bytes
        mov     cnt, #256
.read_loop
        call    #spi_in
        mov     result, cmd          ' Store read byte to result

        ' Optional:  switch between hex print or character print or both
        'call    #print_hex_byte
        call    #uart_tx_char
        call    #uart_tx_space

        djnz    cnt, #.read_loop

        outh    #spi_cs
        ret

' ---- Send 8 bits (MSB first) ----
spi_cmd8
        mov     x, #8
        shl     cmd, #24
        jmp     #spi_cmd

spi_cmd
        rep     @.r, x
        shl     cmd, #1 wc
        outc    #spi_mosi
        waitx   ##45
        outl    #spi_ck          ' falling edge (sample in slave)
        waitx   ##45
        outh    #spi_ck
.r
        ret

' ---- Read 8 bits (MSB first) ----
spi_in
        mov     y, #8
        mov     cmd, #0
.rdloop
        outl    #spi_ck          ' falling edge: sample MISO
        waitx   ##10             ' setup/hold time
        testp   #spi_miso wc
        rcl     cmd, #1
        outh    #spi_ck
        djnz    y, #.rdloop
        ret

' ---- UART hexadecimal Output ----
print_hex_byte
        mov     temp, result
        mov     pr0, temp
        shr     pr0, #4
        and     pr0, #$F
        call    #print_nibble
        mov     pr0, temp
        and     pr0, #$F
        call    #print_nibble
        ret

print_nibble
        cmp     pr0, #10 wc
  if_b  add     pr0, #"0"
  if_nc add     pr0, #"A"-10
        mov     result, pr0
        call    #uart_tx_char
        ret

' ---- UART decimal Output ----
uart_tx_char
        wypin   result, #TX_PIN
.tx
        rdpin   pr2, #TX_PIN wc
  if_c  jmp     #.tx
        ret

uart_tx_space
        mov     result, #" "
        call    #uart_tx_char
        ret

uart_tx_nl
        mov     result, #13
        call    #uart_tx_char
        mov     result, #10
        call    #uart_tx_char
        ret

' ---- End ----
endprog

' ---- General Variables ----
cmd     res 1
x       res 1
y       res 1
temp    res 1
result  res 1
cnt res 1

' ---- Flash Variables ----
RDSR1 res 1
addr    res 1
data    res 1
  • proppyproppy Posts: 37

    Write again, but for a full page (256 bytes):

    CON
  _CLKFREQ  = 180_000_000

  ' UART on P62
  RX_PIN = 63
  TX_PIN = 62
  BAUD_RATE = 2000000
  SERIAL_CLOCK = (_CLKFREQ / BAUD_RATE)
  BIT_PERIOD = ((SERIAL_CLOCK << 16) & $FFFFFC00) + (8 - 1)

  ' SPI pins
  spi_cs   = 8
  spi_ck   = 9
  spi_miso = 10
  spi_mosi = 11
  spi_hld  = 4
  spi_wp   = 5

DAT
org 0
asmclk

' ---- UART TX init ----
        wrpin   ##(P_ASYNC_TX | P_OE), #TX_PIN
        wxpin   ##BIT_PERIOD, #TX_PIN
        wypin   #1, #TX_PIN
        dirh    #TX_PIN

' ---- SPI Init ----
        outh    #spi_cs
        outh    #spi_hld
        outh    #spi_wp

        dirh    #spi_cs
        dirh    #spi_ck
        dirh    #spi_mosi
        dirh    #spi_hld
        dirh    #spi_wp

' ----  Write enable ----
        call #spi_write_enable

' ----  Read Status Register ----
        call #spi_rdsr

' ---- Print ----
    mov     addr, #$0         ' Pick address 0x00

        call    #spi_write_enable

    call #spi_erase_sector

    call #spi_write_enable

    mov     addr, #$0        ' Pick address 0x00
    mov data, #"Z"
    call #spi_byte_write

    mov     result, data
    call    #print_hex_byte
        call    #uart_tx_space

        call    #uart_tx_nl

        jmp     #endprog

' ---- Write Enable ----
spi_write_enable
        outl    #spi_cs          ' CS low

        mov     cmd, #$06
        call    #spi_cmd8        

        outh    #spi_cs          ' CS high
        ret

' ---- READ STATUS REGISTER (RDSR) ----
spi_rdsr
        outl    #spi_cs          ' CS low

        mov     cmd, #$05
        call    #spi_cmd8        

        call    #spi_in
        mov     RDSR1, cmd

        outh    #spi_cs          ' CS high
        ret

spi_erase_sector
        outl    #spi_cs               ' CS low

        mov     cmd, #$20             ' Sector Erase
        call    #spi_cmd8              ' Send command

        call    #spi_send_address24     ' Send address

        outh    #spi_cs        ' CS high

.wait_busy
    call    #spi_rdsr
    testb   RDSR1, #0 wz       ' Test if all bits are 0
  if_z     jmp #.wait_busy    ' Loop again if BUSY/non-ero
  ret                ' Return only when all bits are 0

spi_byte_write       
        outl    #spi_cs          ' CS low

        mov     cmd, #$02          ' WRITE command
        call    #spi_cmd8

        ' Send 24-bit address (A23-A0), top bits don't matter
        mov     cmd, addr
        shr     cmd, #16
        call    #spi_cmd8          ' A23–A16
        mov     cmd, addr
        shr     cmd, #8
        and     cmd, #$FF
        call    #spi_cmd8          ' A15–A8
        mov     cmd, addr
        and     cmd, #$FF
        call    #spi_cmd8          ' A7–A0

        ' Send data byte
        mov     cmd, data
        call    #spi_cmd8

        ' Send the same byte 256 times
        mov     cnt, #256
.page_loop
        mov     cmd, data
        call    #spi_cmd8
        djnz    cnt, #.page_loop

        outh    #spi_cs          ' CS high (starts write)
        ret


        ' ---- Send 24-bit address ----
spi_send_address24
        mov     cmd, addr
        shr     cmd, #16
        call    #spi_cmd8      ' A23–A16
        mov     cmd, addr
        shr     cmd, #8
        and     cmd, #$FF
        call    #spi_cmd8      ' A15–A8
        mov     cmd, addr
        and     cmd, #$FF
        call    #spi_cmd8      ' A7–A0

        ret


' ---- Send 8 bits (MSB first) ----
spi_cmd8
        mov     x, #8
        shl     cmd, #24
        jmp     #spi_cmd

spi_cmd
        rep     @.r, x
        shl     cmd, #1 wc
        outc    #spi_mosi
        waitx   ##45
        outl    #spi_ck          ' falling edge (sample in slave)
        waitx   ##45
        outh    #spi_ck
.r
        ret

' ---- Read 8 bits (MSB first) ----
spi_in
        mov     y, #8
        mov     cmd, #0
.rdloop
        outl    #spi_ck          ' falling edge: sample MISO
        waitx   ##10             ' setup/hold time
        testp   #spi_miso wc
        rcl     cmd, #1
        outh    #spi_ck
        djnz    y, #.rdloop
        ret

' ---- UART hexadecimal Output ----
print_hex_byte
        mov     temp, result
        mov     pr0, temp
        shr     pr0, #4
        and     pr0, #$F
        call    #print_nibble
        mov     pr0, temp
        and     pr0, #$F
        call    #print_nibble
        ret

print_nibble
        cmp     pr0, #10 wc
  if_b  add     pr0, #"0"
  if_nc add     pr0, #"A"-10
        mov     result, pr0
        call    #uart_tx_char
        ret

' ---- UART character Output ----
uart_tx_char
        wypin   result, #TX_PIN
.tx
        rdpin   pr2, #TX_PIN wc
  if_c  jmp     #.tx
        ret

uart_tx_space
        mov     result, #" "
        call    #uart_tx_char
        ret

uart_tx_nl
        mov     result, #13
        call    #uart_tx_char
        mov     result, #10
        call    #uart_tx_char
        ret

' ---- End ----
endprog

' ---- General Variables ----
cmd     res 1
x       res 1
y       res 1
temp    res 1
result  res 1
cnt res 1

' ---- Flash Variables ----
RDSR1 res 1
addr    res 1
data    res 1

    I decided to do a write without the erase for the spi flash just to see what the "corruption" might look like. A 41, and then a write without erase stored at 40. The Flash 6 click just happened to be the Winbond W25Q128JV. Fun stuff. Still needs some clean up.

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