add comments

platformio.ini

@@ -81,7 +81,11 @@ framework = arduino
 board_build.partitions = partitions/esp32_partition_32M.csv
 
 [env]
-platform = https://github.com/tasmota/platform-espressif32/releases/download/2026.09.50/platform-espressif32.zip ; Arduino Core 3.3.12 based on IDF 5.5.5
+; use own Ardunio libs packages from https://github.com/emsesp/esp32-arduino-lib-builder which is based on Arduino Core 3.3.12 and IDF 5.5.5. Same as s_16M_P_custom
+; with Tasmota's tool chain (platform)
+; if we want to go back to Tasmota libs, use the following:
+; platform = https://github.com/tasmota/platform-espressif32/releases/download/2026.05.50/platform-espressif32.zip ; Tasmota Arduino Core 3.3.8 based on IDF 5.5.4.260407
+platform = https://github.com/tasmota/platform-espressif32/releases/download/2026.09.50/platform-espressif32.zip
 platform_packages = framework-arduinoespressif32 @ https://github.com/emsesp/esp32-arduino-lib-builder/releases/download/0910-1604-5.5.5/framework-arduinoespressif32-v5.5.5-a63b839f.tar.xz
 build_flags =
   ${common.build_flags}
@@ -133,6 +137,7 @@ board = s_16M_P
 
 [env:s_16M_P_custom]
 ; same as s_16M_P, but the Arduino/IDF libs are rebuilt with HybridCompile using the custom_sdkconfig below
+; this is same procedure as in the esp32-arduino-lib-builder repository
 extends = env:s_16M_P
 custom_sdkconfig =
   '# CONFIG_BT_ENABLED is not set'
@@ -155,6 +160,8 @@ custom_sdkconfig =
   '# CONFIG_I2S_ISR_IRAM_SAFE is not set'
   '# CONFIG_RINGBUF_PLACE_ISR_FUNCTIONS_INTO_FLASH is not set'
   'CONFIG_UART_ISR_IN_IRAM=y'
+  'CONFIG_SPIRAM_MALLOC_ALWAYSINTERNAL=256'
+  'CONFIG_SPIRAM_MALLOC_RESERVE_INTERNAL=1024'
 
 [env:s3_16M_P]
 ; 16MB ESP32-S3 - with PSRAM - like a BBQKees S3