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philippe44 3 年之前
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      README.md

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README.md

@@ -251,7 +251,7 @@ Syntax is:
 You can define the defaults for jack, spkfault leds at compile time but nvs parameter takes precedence except for well-known configurations where these are forced at runtime.
 **Note that gpio 36 and 39 are input only and cannot use interrupt. When set to jack or speaker fault, a 100ms polling checks their value but that's expensive**
 ### GPIO expander (not fully validated yet)
-It is possible to add GPIO expanders using I2C bus. They should mainly be used for buttons but they can support generic-purpose outputs as well (NOT YET). These additional GPIOs can be numbered starting from an arbitrary value (100 min). Then these new "virtual" GPIOs from (e.g) 100 to 115 can be used in button configuration, set_GPIO or other config settings.
+It is possible to add GPIO expanders using I2C bus. They should mainly be used for buttons but they can support generic-purpose outputs as well (NOT YET). These additional GPIOs can be numbered starting from an arbitrary value (40 and above as esp32 has GPIO 0..39). Then these new "virtual" GPIOs from (e.g) 100 to 115 can be used in button configuration, set_GPIO or other config settings.
 
 Each expander (ONLY ONE FOR NOW) can support up to 32 GPIO. To use an expander for buttons, an interrupt must be provided, polling mode is not acceptable. An expander w/o interruption can still be configured, but only output will be usable.
 
@@ -262,8 +262,8 @@ model=<model>,addr=<addr>,[,port=<system|dac>][,base=<n|100>][,count=<n|16>][,in
 - model: pca9535 (only tested today), pca85xx (untested) and mcp23017 (soon)
 - addr: inthe i2c address decimal 	
 - port: use either "system" port (shared with display for example) or "dac" port (system is default)
-- base: GPIO numbering offset to use everywhere else (default 100)
-- count: number of GPIO of expander (default 16 - might be obsolted if model if sufficient)
+- base: GPIO numbering offset to use everywhere else (default 40)
+- count: number of GPIO of expander (default 16 - might be obsolted if model if sufficient to decide)
 - intr: real GPIO to use as interrupt.
 	
 Note that PWM ("led_brightness" below) is not supported for expanded GPIOs, neither connecting them to a rotary encoder (for speed reason). Depending on the actual chipset, pullup or pulldown might be supported