diff --git a/ports/mimxrt/boards/ADAFRUIT_METRO_M7/mpconfigboard.h b/ports/mimxrt/boards/ADAFRUIT_METRO_M7/mpconfigboard.h
index ac9cf9705807..7d759df5e6f4 100644
--- a/ports/mimxrt/boards/ADAFRUIT_METRO_M7/mpconfigboard.h
+++ b/ports/mimxrt/boards/ADAFRUIT_METRO_M7/mpconfigboard.h
@@ -23,6 +23,12 @@
     { 0 }, { 0 }, \
     { IOMUXC_GPIO_AD_02_LPUART4_TXD }, { IOMUXC_GPIO_AD_01_LPUART4_RXD },
 
+#define IOMUX_TABLE_UART_CTS_RTS \
+    { IOMUXC_GPIO_08_LPUART1_CTS_B }, { IOMUXC_GPIO_07_LPUART1_RTS_B }, \
+    { IOMUXC_GPIO_AD_14_LPUART3_CTS_B }, { 0 }, \
+    { 0 }, { 0 }, \
+    { IOMUXC_GPIO_AD_14_LPUART4_CTS_B }, { 0 },
+
 #define MICROPY_HW_SPI_INDEX { 1 }
 
 #define IOMUX_TABLE_SPI \
diff --git a/ports/mimxrt/boards/OLIMEX_RT1010/mpconfigboard.h b/ports/mimxrt/boards/OLIMEX_RT1010/mpconfigboard.h
index 828855d4d361..9443bb373271 100644
--- a/ports/mimxrt/boards/OLIMEX_RT1010/mpconfigboard.h
+++ b/ports/mimxrt/boards/OLIMEX_RT1010/mpconfigboard.h
@@ -26,10 +26,10 @@
     { IOMUXC_GPIO_06_LPUART4_TXD }, { IOMUXC_GPIO_05_LPUART4_RXD },
 
 #define IOMUX_TABLE_UART_CTS_RTS \
-    { IOMUXC_GPIO_AD_B0_14_LPUART1_CTS_B }, { IOMUXC_GPIO_AD_B0_15_LPUART1_RTS_B }, \
+    { IOMUXC_GPIO_08_LPUART1_CTS_B }, { IOMUXC_GPIO_07_LPUART1_RTS_B }, \
     { 0 }, { 0 }, \
     { 0 }, { 0 }, \
-    { IOMUXC_GPIO_EMC_17_LPUART4_CTS_B }, { IOMUXC_GPIO_EMC_18_LPUART4_RTS_B },
+    { IOMUXC_GPIO_AD_14_LPUART4_CTS_B }, { IOMUXC_GPIO_AD_13_LPUART4_RTS_B },
 
 #define MICROPY_HW_SPI_INDEX { 0, 1, 2 }