diff --git a/platformio.ini b/platformio.ini
index f31e790..9d4cb46 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -270,7 +270,7 @@ monitor_echo = yes
 ; Experimental - Ethernet work still in progress
 ;
 [env:Nucleo-F429ZI]
-platform = ststm32 @ ^18.0.0
+platform = ststm32 @ 19.0.0
 board = nucleo_f429zi
 framework = arduino
 lib_deps = ${env.lib_deps}
@@ -281,7 +281,7 @@ lib_ignore = WiFi101
 			WiFiEspAT
 			WiFiMulti_Generic
 			WiFiNINA_Generic
-build_flags = -std=c++17 -Os -g2 -Wunused-variable
+build_flags = -std=c++17 -Os -g2 -Wunused-variable -DCUSTOM_PERIPHERAL_PINS
 monitor_speed = 115200
 monitor_echo = yes
 upload_protocol = stlink
@@ -289,7 +289,7 @@ upload_protocol = stlink
 ; Experimental - Ethernet work still in progress
 ;
 [env:Nucleo-F439ZI]
-platform = ststm32 @ ^18.0.0
+platform = ststm32 @ 19.0.0
 ; board = nucleo_f439zi
 ; Temporarily treat it as an F429ZI (they are code compatible) until
 ; the PR to PlatformIO to update the F439ZI JSON file is available
@@ -304,7 +304,7 @@ lib_ignore = WiFi101
 			WiFiEspAT
 			WiFiMulti_Generic
 			WiFiNINA_Generic
-build_flags = -std=c++17 -Os -g2 -Wunused-variable
+build_flags = -std=c++17 -Os -g2 -Wunused-variable -DCUSTOM_PERIPHERAL_PINS
 monitor_speed = 115200
 monitor_echo = yes
 upload_protocol = stlink