FotS

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==== Three Output States from One Pin====
See this thread for the original discussion/design of using one pin,set to  High,Low or Hi Impedance to generate three output states to allow control to two outputs. Handy if you are short 1 pin. Initially used on the Picomite to use a single pin to control both Touch CS and SD CS on an LCD Panel. \\
[[https://www.thebackshed.com/forum/ViewTopic.php?TID=16691&P=2|A new Pico PCB for V5.09.00 - comments]]\\

**The Truth Table**\\
^ Pin Status           ^ Output 1  ^ Output 2  ^
| HiZ (set as input)   | 1         | 1         |
| 0   (set as output)  | 0         | 1         |
| 1   (set as output)  | 1         | 0         |

**The circuit** (courtesy @Turbo46 on TBS)\\
//Note1: The symbol for Q3 is incorrect, should be an NPN the same as Q2//\\
//Note2: Change all 10K to 1K and all 100K to 10K//
{{https://www.thebackshed.com/forum/uploads/Turbo46/2024-02-14_151448_Matherp1.png}}

The circuit works when you change Q3 into an NPN transistor.
Works perfectly. I've substituted 1k for all 10K and 10K for all 100K
Three output states from one pin
{{https://www.thebackshed.com/forum/uploads/matherp/2024-02-14_220010_PXL_20240210_191321546.jpg}}

{{https://www.thebackshed.com/forum/uploads/matherp/2024-02-14_220126_Image6.jpg}}