From 775c815e1e8b2a5608372adc46139965da02560a Mon Sep 17 00:00:00 2001 From: andrethomas Date: Sat, 28 Jul 2018 21:00:36 +0200 Subject: [PATCH] Updated MCP23008 MCP23017 (markdown) --- MCP23008-MCP23017.md | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/MCP23008-MCP23017.md b/MCP23008-MCP23017.md index 48e9e607..826eb23f 100644 --- a/MCP23008-MCP23017.md +++ b/MCP23008-MCP23017.md @@ -92,7 +92,11 @@ Where: **1** = Weak internal pull-up **ENABLED** -Examples of this: +### IMPORTANT NOTICE ON USE OF INTERRUPTS + +**_Only use interrupts on pins which are either explicitly pulled down GND or up to VCC externally as floating pins may cause unintended MQTT responses for pins which are floating. So unless your connected wire/device explicitly pulls the pin to GND or VCC only when conditions of an interrupt would be met it is recommended that you either do not set a pin for an interrupt mode or at least enable pull-up resistors for the unused pins with pullup = 1 when you perform your sensor29 pin,pinmode,pullup command._** + +Examples of some pin configuration options: `sensor29 4,1,0` - Will enable D4 for INPUT without internal pull-up resistor