Shop OBEX P1 Docs P2 Docs Learn Events
The unofficial P2 documentation project - Page 13 — Parallax Forums

The unofficial P2 documentation project

1789101113»

Comments

  • SeairthSeairth Posts: 2,474
    edited 2013-05-21 03:20
    Oh! That list! After all the detailed stuff post by Chip, I'd forgotten about that PDF.
  • SeairthSeairth Posts: 2,474
    edited 2013-05-23 17:21
    For instructions like SETPNZ, SETPORT, SETXFR, etc., where the parameter is encoded in the D field (000011 ZCN 1 CCCC DDnnnnnnn 011011111), does the non-immediate (N=0) encoding allow for using INDA/INDB? Put another way, are these instructuctions internally remapped as follows:

    N -> I
    DDnnnnnnn -> SSnnnnnnn

    And if this is all true, then does this mean that the instruction is actually decoded in the same stage that INDA/INDB fix-ups occur (stage 2)?
  • cgraceycgracey Posts: 14,151
    edited 2013-05-24 08:40
    Seairth wrote: »
    For instructions like SETPNZ, SETPORT, SETXFR, etc., where the parameter is encoded in the D field (000011 ZCN 1 CCCC DDnnnnnnn 011011111), does the non-immediate (N=0) encoding allow for using INDA/INDB? Put another way, are these instructuctions internally remapped as follows:

    N -> I
    DDnnnnnnn -> SSnnnnnnn

    And if this is all true, then does this mean that the instruction is actually decoded in the same stage that INDA/INDB fix-ups occur (stage 2)?

    That funny-looking DDnnnnnn just shows that in the case of immediate, only the 7 LSBs are used, whereas all 9 bits are used for a register (which could be indirect).
  • Cluso99Cluso99 Posts: 18,069
    edited 2013-05-29 19:38
    While looking over my instruction table I found a couple of errors...
    MUL and SCL and their shared instructions references to the i bit should refer to the r bit.
    Opcodes 000011 references to the r bit should refer to the i bit

    P2_Instructions.spin
  • evanhevanh Posts: 15,912
    edited 2013-09-21 03:10
    I'm just starting to read the The unofficial P2 documentation project - https://docs.google.com/document/pub?id=1-9OtOVRkTxojO-cAFMwpcZEUorkCU_uwi26EQZMV8uM#h.c02grsesnwwf

    For the multitasking instructions and descriptions I think there should be a distinction in the naming between the hardware time slicing and software context switching. "Task" is used in naming of both mechanisms. This makes for difficult reading for anyone not already understanding of how it all works.

    How about referring to, the nominally cooperative, software context switching as "tasks" and hardware time slicing as "threads"? Will need the instructions themselves relabelled too.
  • evanhevanh Posts: 15,912
    edited 2013-09-21 05:52
    Now that I've found Ghostery I'm a bit more prepared to enable scripting on rare occasions ... well, I just tried it with Google Docs ... boy was that a shock! It reminds me of trying to do DTP with a 0.5 MIPS processor. I'm run a 3.3 GHz (>10000 MIPS?) processor with multi-GB/s RAM speed and still being blown away by how bad bloat gets! :( How did this document get built?

    NoScript is back in lock down mode thank you very much.
Sign In or Register to comment.