In SX Microcontrollers, SX/B Compiler and SX-Key Tool, JonnyMac wrote:

In SX/B the you must preset the clock line for SHIFTIN and SHIFTOUT as those routines simply invert it. Also, you're adding the two result bytes together so you can never get anything beyond 255, and with all the division you do after I'm surprised you get anything but zero.

Let me suggest you update your code like this:

Dio             PIN     RC.4 INPUT
Clk             PIN     RC.3 OUTPUT
CS              PIN     RC.2 OUTPUT

result          VAR     Word
thC             VAR     Word

' =============
  PROGRAM Start
' =============

Start:
  CS = 1

Main:
  PAUSE 1
  Clk = 0
  CS = 0
  SHIFTIN  Dio, Clk, MSBPOST, result_MSB
  SHIFTIN  Dio, Clk, MSBPOST, result_LSB
  CS = 1

  thC = result >> 3
  thC = thC */ 640
  thC = thC / 10

  'BREAK
  GOTO Main


The data sheet suggests reading a bit after the falling edge of the clock, hence MSBPOST. Note that when you declare a word in SX/B that it creates to byte aliases for the _LSB and _MSB and that's what are used in the SHIFTIN calls. Once you get this working you can modify the SHIFTIN with the speed multiplier to increase the transmission speed.

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