1 files changed, 20 insertions, 5 deletions

diff --git a/stmhal/adc.c b/stmhal/adc.c
index 39f0364078..bcf8956254 100644
--- a/stmhal/adc.c
+++ b/stmhal/adc.c
@@ -54,7 +54,16 @@
 #define ADCx                    (ADC1)
 #define ADCx_CLK_ENABLE         __ADC1_CLK_ENABLE
 #define ADC_NUM_CHANNELS        (19)
-#define ADC_NUM_GPIO_CHANNELS   (16)
+
+#if defined(MCU_SERIES_F4) || defined(MCU_SERIES_F7)
+#define ADC_FIRST_GPIO_CHANNEL  (0)
+#define ADC_LAST_GPIO_CHANNEL   (15)
+#elif defined(MCU_SERIES_L4)
+#define ADC_FIRST_GPIO_CHANNEL  (1)
+#define ADC_LAST_GPIO_CHANNEL   (16)
+#else
+#error Unsupported processor
+#endif
 
 #if defined(STM32F405xx) || defined(STM32F415xx) || \
     defined(STM32F407xx) || defined(STM32F417xx) || \
@@ -124,7 +133,7 @@ STATIC void adc_init_single(pyb_obj_adc_t *adc_obj) {
         return;
     }
 
-    if (adc_obj->channel < ADC_NUM_GPIO_CHANNELS) {
+    if (ADC_FIRST_GPIO_CHANNEL <= adc_obj->channel && adc_obj->channel <= ADC_LAST_GPIO_CHANNEL) {
       // Channels 0-16 correspond to real pins. Configure the GPIO pin in
       // ADC mode.
       const pin_obj_t *pin = pin_adc1[adc_obj->channel];
@@ -253,8 +262,14 @@ STATIC mp_obj_t adc_make_new(const mp_obj_type_t *type, mp_uint_t n_args, mp_uin
     if (!is_adcx_channel(channel)) {
         nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "not a valid ADC Channel: %d", channel));
     }
-    if (pin_adc1[channel] == NULL) {
-        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "channel %d not available on this board", channel));
+
+
+    if (ADC_FIRST_GPIO_CHANNEL <= channel && channel <= ADC_LAST_GPIO_CHANNEL) {
+        // these channels correspond to physical GPIO ports so make sure they exist
+        if (pin_adc1[channel] == NULL) {
+            nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_ValueError,
+                "channel %d not available on this board", channel));
+        }
     }
 
     pyb_obj_adc_t *o = m_new_obj(pyb_obj_adc_t);
@@ -423,7 +438,7 @@ void adc_init_all(pyb_adc_all_obj_t *adc_all, uint32_t resolution) {
                 "resolution %d not supported", resolution));
     }
 
-    for (uint32_t channel = 0; channel < ADC_NUM_GPIO_CHANNELS; channel++) {
+    for (uint32_t channel = ADC_FIRST_GPIO_CHANNEL; channel <= ADC_LAST_GPIO_CHANNEL; ++channel) {
         // Channels 0-16 correspond to real pins. Configure the GPIO pin in
         // ADC mode.
         const pin_obj_t *pin = pin_adc1[channel];