From b2b4c9e0f73bd9d5a435b291ee27574ee9c2f69f Mon Sep 17 00:00:00 2001
From: jgromes <jan.gromes@gmail.com>
Date: Fri, 27 Dec 2024 16:26:24 +0000
Subject: [PATCH] [SX126x] Use dummy SPI transfer for wakeup (#1364)

---
 src/modules/SX126x/SX126x.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/modules/SX126x/SX126x.cpp b/src/modules/SX126x/SX126x.cpp
index 1d8c0801..31aa2aa3 100644
--- a/src/modules/SX126x/SX126x.cpp
+++ b/src/modules/SX126x/SX126x.cpp
@@ -467,8 +467,10 @@ int16_t SX126x::standby(uint8_t mode, bool wakeup) {
   this->mod->setRfSwitchState(Module::MODE_IDLE);
 
   if(wakeup) {
-    // pull NSS low to wake up
-    this->mod->hal->digitalWrite(this->mod->getCs(), this->mod->hal->GpioLevelLow);
+    // send a NOP command - this pulls the NSS low to exit the sleep mode,
+    // while preventing interference with possible other SPI transactions
+    // see https://github.com/jgromes/RadioLib/discussions/1364
+    (void)this->mod->SPIwriteStream(RADIOLIB_SX126X_CMD_NOP, NULL, 0, false, false);
   }
 
   uint8_t data[] = { mode };