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HadCon Multipurpose Controls Protocol Cmnd Apfel Details Of The Protocol

Introduction

The communication with the APFEL chip on the signal level

Main

Bits

Bits are represented by a sequence of 5 states of the pins DOUT and CLK

High

  1. DOUT low + CLK low
  2. DOUT high + CLK low
  3. DOUT high + CLK high
  4. DOUT low + CLK high
  5. DOUT low + CLK low

Low

  1. DOUT low + CLK low
  2. DOUT high + CLK low
  3. DOUT high + CLK high
  4. DOUT low + CLK high
  5. DOUT low + CLK low

Measurements

Bits.png
  • ~25μs per bit
    • → max 40kBit/s
  • + 10µs
    • → max 28kBit/s

execution times of the api

  • using artificial markers before and after the parser give
    • a minimum of ~37µs per call
    • typical values of ~1.2ms (w/o any output)
    • typical values of ~12 ms (with output)
    • typical values of ~15 ms (with error output)
    • maximum 125ms (autocalibration)

commands

The naked commands of the APFEL protocol is a big-endian sequence of 22 bits:
  1. 4 command bits
  2. 10 value bits
  3. 8 chip id bits

This sequence is prefixed by a stream header consisting of
  1. a clear data input, i.e.
    1. for each command sequence bit (22)
      • write 1 clock sequence:
        1. write 1 low bit
      • each 8 bit with 2 additional sequences of
        • DOUT low + CLK low
    2. followed by 10 sequences of the same
      • DOUT low + CLK low


-- PeterZumbruch - 30 Mar 2015
-- PeterZumbruch - 2015-03-30
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Bits.pngpng Bits.png manage 5.6 K 2015-03-30 - 09:55 PeterZumbruch Bit timing
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Topic revision: r2 - 2015-03-30, PeterZumbruch
 
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