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P2 Boot Options / Sequence/ Pull-ups / Pull-downs — Parallax Forums

P2 Boot Options / Sequence/ Pull-ups / Pull-downs

ke4pjwke4pjw Posts: 1,155
edited 2018-09-28 14:11 in Propeller 2
Is this documentation for booting the P2 correct?
P61 spi-CS sd-CK pu = spi flash
P60 spi-CK sd-CS pu = SD card (pullup is internal on the card)
P59 spi-DI sd-DI pu = Serial pd = Stop
P58 spi-DO sd-DO

P59 pullup = goto Serial
P60 pullup = goto SD card
P61 pullup = goto SPI Flash
P59 pulldn = Stop
else = goto Serial

Looks like there were some very last minute changes to the boot options just before the ROM was shipped to On-Semi in May.

Discussion found here: http://forums.parallax.com/discussion/162298/prop2-fpga-files-updated-2-june-2018-final-version-32i/p139

Do we know if P59 was floating when chip was attempting to program the P2 last night? Might that have been detected as a pd and forced serial to not work?

Chip, Ken, et al, thank you so much for sharing the live stream yesterday. You guys were up on the 62" TV most of the evening, much to the chagrin of my wife and kids. They didn't understand my excitement :)

Comments

  • RaymanRayman Posts: 14,644
    Hey, I think you've found the problem...

    Definitely need a pullup on P59...
  • Cluso99Cluso99 Posts: 18,069
    edited 2018-09-28 15:33
    Here is my recollection from the final FPGA testing and rom code. I haven't checked the code or FPGA yet.

    I used the Propeller Serial Terminal for most of my testing.

    A reset can be issued by toggling DTR.

    Then the sequence to identify the prop is preferred (cannot recall exact char sequence) to be sent. This sets the autobaud in P2. Then IIRC an <esc> will pass control to TAQOZ, or Ctl-D will pass control to my debug/monitor. Both TAQOZ and MONITOR identify themselves so you know you're there. You can go between TAQOZ and MONITOR by the same keys (Monitor requires <esc> followed by <cr>).

    Chip, I hope this refreshes your memory.

    IIRC a memory dump is
    100 L<cr>
    100 . 180 L<cr>
    00100 . 00180 L<cr>
    spaces shown are not required

    Postedit: fixed syntax
  • Cluso99Cluso99 Posts: 18,069
    We were not able to properly test the pull-ups and pulldowns as the FPGA had internal side effects on P58-P63.

    But it should not have been necessary to have a pull-up on P59 IIRC. Perhaps the ROM code is waiting too long after returning P59 direction to input before sampling the pin, or the analog is providing a higher pulldown resistance than anticipated.

    Anyway, we can certainly test the times and values required for the various boot options.
  • ke4pjwke4pjw Posts: 1,155
    I wonder if the P59 PU is only needed if programming or communicating with serial. If that is the case, once SPI Flash or SD is written with boot code, maybe it can boot off of those devices without a P59 PU.
  • ozpropdevozpropdev Posts: 2,792
    Cluso
    Was there a late change to the monitor syntax?
    I'm not seeing any response here. (Nano with latest FPGA image) 
    Prop_Ver C

P2-MONITOR V1.0
*100L
!
*100.180L
?
*00100.00180L
?
  • Peter JakackiPeter Jakacki Posts: 10,193
    The FPGAs work so nothing has changed but real silicon seems to have some kind of loading or something that necessitates a pullup. There's also the 70ma+ current draw even in RCFAST etc that wasn't expected.
  • garryjgarryj Posts: 337
    ozpropdev wrote: »
    Cluso
    Was there a late change to the monitor syntax?
    I'm not seeing any response here. (Nano with latest FPGA image) 
    Prop_Ver C

P2-MONITOR V1.0
*100L
!
*100.180L
?
*00100.00180L
?
    100-180L for a long listing
    00100-00180m for a byte listing
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