In SX Microcontrollers, SX/B Compiler and SX-Key Tool, Capt. Quirk wrote:

Sorry Jon and Terry.

Berfore this thread it was my impression that ADC's and other devices that used ShiftIn & Shiftout only used ShiftIn to transfer it's data to the SX (correctly). I had never thought about the time a chip, like the max6675 did in between Shiftin cycles. Until I read the 6675 data sheet and it said that bringing CS low cuts off any conversion that is in process and that CS high would start the conversion process.

So, I thought there had to be a clock source to make the 6675's conversion process work and that's why I (incorrectly) thought speeding up the clock speed would eliminate the calculation delay of the 6675 chip.

But Jon's code, only showed 16 clock cycles and Bean's comment about racing between stop lights made sense. So now I know that the 6675 really is that slow. Also Jon's comments about designing your code around a manufactures worst case, is very necessary and how important it is to understand a data sheet before I buy any new chips again. Also I now understand how these style devices work and exactly how to write code for them because of your help.  

Thank you very much

Sincerely

Bill Mazzacane

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