From c5da1a9c0a87e548ee1c2fa52e348797d355dc28 Mon Sep 17 00:00:00 2001 From: Nathan Seidle Date: Thu, 24 Oct 2019 14:44:03 -0600 Subject: [PATCH] Increase pullup resistor on RX pin On some GPIO the g_AM_HAL_GPIO_INPUT_PULLUP seems to be strong enough to cause problems with translation buffers like the TXB0104. Limiting to 24k fixing issue. --- libraries/SoftwareSerial/src/SoftwareSerial.cpp | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/libraries/SoftwareSerial/src/SoftwareSerial.cpp b/libraries/SoftwareSerial/src/SoftwareSerial.cpp index a1c2e801..4dbc44e4 100644 --- a/libraries/SoftwareSerial/src/SoftwareSerial.cpp +++ b/libraries/SoftwareSerial/src/SoftwareSerial.cpp @@ -122,7 +122,13 @@ void SoftwareSerial::begin(uint32_t baudRate, HardwareSerial_Config_e SSconfig) pinMode(_rxPin, INPUT); if (_invertLogic == false) - pinMode(_rxPin, INPUT_PULLUP); //Enable external pullup if using normal logic + { + //Enable external pullup if using normal logic + //On some GPIO the g_AM_HAL_GPIO_INPUT_PULLUP seems to be strong enough + //to cause problems translation buffers like the TXB0104. Limiting + //to 24k fixing issue. + pinMode(_rxPin, g_AM_HAL_GPIO_INPUT_PULLUP_24); + } #ifdef DEBUG am_hal_gpio_output_clear(debugPad);