diff --git a/os/hal/ports/STM32/LLD/GPIOv2/hal_pal_lld.c b/os/hal/ports/STM32/LLD/GPIOv2/hal_pal_lld.c
index b3ca69b8f..7cd343f51 100644
--- a/os/hal/ports/STM32/LLD/GPIOv2/hal_pal_lld.c
+++ b/os/hal/ports/STM32/LLD/GPIOv2/hal_pal_lld.c
@@ -177,7 +177,7 @@ void _pal_lld_setgroupmode(ioportid_t port,
       port->OTYPER  = (port->OTYPER & ~m1) | otyper;
       port->OSPEEDR = (port->OSPEEDR & ~m2) | ospeedr;
       port->PUPDR   = (port->PUPDR & ~m2) | pupdr;
-      if (moder == PAL_STM32_MODE_ALTERNATE) {
+      if ((mode & PAL_STM32_MODE_MASK) == PAL_STM32_MODE_ALTERNATE) {
         /* If going in alternate mode then the alternate number is set
            before switching mode in order to avoid glitches.*/
         if (bit < 8)
diff --git a/os/hal/ports/STM32/LLD/GPIOv3/hal_pal_lld.c b/os/hal/ports/STM32/LLD/GPIOv3/hal_pal_lld.c
index 7b85fe45f..e55c0c697 100644
--- a/os/hal/ports/STM32/LLD/GPIOv3/hal_pal_lld.c
+++ b/os/hal/ports/STM32/LLD/GPIOv3/hal_pal_lld.c
@@ -163,7 +163,7 @@ void _pal_lld_setgroupmode(ioportid_t port,
       port->ASCR    = (port->ASCR & ~m1) | ascr;
       port->OSPEEDR = (port->OSPEEDR & ~m2) | ospeedr;
       port->PUPDR   = (port->PUPDR & ~m2) | pupdr;
-       if (moder == PAL_STM32_MODE_ALTERNATE) {
+       if ((mode & PAL_STM32_MODE_MASK) == PAL_STM32_MODE_ALTERNATE) {
         /* If going in alternate mode then the alternate number is set
            before switching mode in order to avoid glitches.*/
         if (bit < 8)
diff --git a/readme.txt b/readme.txt
index 18488a711..dcb5f1a72 100644
--- a/readme.txt
+++ b/readme.txt
@@ -153,6 +153,8 @@
 - RT:  Merged RT4.
 - NIL: Merged NIL2.
 - NIL: Added STM32F7 demo.
+- HAL: Fixed setting alternate mode in STM32 GPIOv3 and GPIOv3 drivers can fail
+       (bug #813)(backported to 16.1.7).
 - HAL: Fixed incorrect handling of shared ISRs in STM32 DMAv1 driver
        (bug #812)(backported to 16.1.7).
 - HAL: Fixed protocol violation in usbDisableEndpointsI() API (bug #811)