Shop OBEX P1 Docs P2 Docs Learn Events
PropII counters — Parallax Forums

PropII counters

Cluso99Cluso99 Posts: 18,069
edited 2009-02-13 09:21 in Propeller 1
Chip:

I know you have discussed improvements to the video counters for more color bits. However, I don't think·this option·has been raised before, although lots have asked about high speed inter-prop communications.

I have not programmed the counters on the Prop I before. I have just found that to use one counter to gate the other within the same prop it is necessary to waste a pin. So, would it be possible to include a mode like PLL that drives the Video directly, to also have a direct connection to the other counter without using an external·pin?

Also, because I am trying to do high speed comms between props, it would be useful to have a mode that can shift in or out, the phsx register, a bit at a time. (i.e. bit 31 output and shift left each clock (PLL source from the other counter or it's own counter would even be better). This way we could have a sort of UART function running automatically in one cog. Counter A could be used to output up to 32 bits plus start and stop, counter B could be used to input up to 32 bits, plus start and stop bits. The FRQx could be used as a buffer to store the next transmitted char/long or the last received char/long. May need a waitfrq instruction???

It may also be nice to be able to use the video counters in reverse - i.e. shift in as well as shift out.



▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Links to other interesting threads:

· Home of the MultiBladeProps (SixBladeProp)
· Prop Tools under Development or Completed (Index)
· Emulators (Micros eg Altair, and Terminals eg VT100) - index
· Search the Propeller forums (via Google)

My cruising website is: ·www.bluemagic.biz

Comments

  • cgraceycgracey Posts: 14,141
    edited 2009-02-13 08:31
    It sounds like you are mainly interested in chip-to-chip communications. I've been thinking about·fast serial comms·and the smoothest way to add them is, as you suggested, by augmenting the video generator, maybe even using the color lookup-table RAM as a FIFO. 8/16/32-bit data can be sent at over 100MHz this way, using a 3x overclock for reception.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔


    Chip Gracey
    Parallax, Inc.
  • Cluso99Cluso99 Posts: 18,069
    edited 2009-02-13 09:21
    Exactly smile.gif

    8/16/32bit would be great for prop to prop, whereas 8 bit for the UARTs to pc, etc would be great.

    We need to be able to do full duplex (send and receive simultaneously - makes the protocol overhead simpler). And wow - a set in each cog !!!

    A extra prop ends up being cheap if you can do multiple things with it. This is where I am up to - adding more I/O, generating a common clock (5 or 6MHz -·no expensive xtal oscillator), loading code (no need for more I2C) and freeing up those pins, and adding SRAM and microSD. So this is why I want fast comms between props. While what I am aiming at presently is not mainstream, I think it will open up a lot of other interesting applications.

    The more I get into these Props, the more excited I get. Thanks Chip :-)

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Links to other interesting threads:

    · Home of the MultiBladeProps (SixBladeProp)
    · Prop Tools under Development or Completed (Index)
    · Emulators (Micros eg Altair, and Terminals eg VT100) - index
    · Search the Propeller forums (via Google)

    My cruising website is: ·www.bluemagic.biz

    Post Edited (Cluso99) : 2/13/2009 9:30:16 AM GMT
Sign In or Register to comment.