some comments

platform/hw_utils.c

@@ -240,34 +240,45 @@ char * pinmask2str_up(uint32_t pins, char *buffer)
     return buffer;
 }
 
-/** Spread packed port pins using a mask */
-uint32_t pinmask_spread(uint32_t packed, uint32_t mask)
+/** spread a packed pinfield using a mask */
+uint32_t pinmask_spread_32(uint32_t packed, uint32_t mask)
 {
     uint32_t result = 0;
     uint32_t poke = 1;
+    if(packed == 0) return 0;
+
     for (int i = 0; i<32; i++) {
-        if (mask & (1<<i)) {
+        if (mask & 1) {
             if (packed & poke) {
                 result |= 1<<i;
+                packed ^= poke;
+                if (packed == 0) break;
             }
             poke <<= 1;
         }
+        mask >>= 1;
+        // if (mask == 0) break;
     }
+
     return result;
 }
 
 /** Pack spread port pins using a mask */
-uint32_t pinmask_pack(uint32_t spread, uint32_t mask)
+uint32_t pinmask_pack_32(uint32_t spread, uint32_t mask)
 {
     uint32_t result = 0;
     uint32_t poke = 1;
     for (int i = 0; i<32; i++) {
-        if (mask & (1<<i)) {
+        if (mask & 1) {
             if (spread & (1<<i)) {
                 result |= poke;
+                spread ^= (1<<i);
+                if (spread == 0) break;
             }
             poke <<= 1;
         }
+        mask >>= 1;
+        // if (mask == 0) break;
     }
     return result;
 }

platform/hw_utils.h

@@ -98,7 +98,12 @@ char * pinmask2str_up(uint32_t pins, char *buffer);
  * @param mask - positions of the bits (eg. 0x8803)
  * @return - bits spread to their positions (always counting from right)
  */
-uint32_t pinmask_spread(uint32_t packed, uint32_t mask);
+uint32_t pinmask_spread_32(uint32_t packed, uint32_t mask);
+
+static inline uint16_t pinmask_spread(uint16_t packed, uint16_t mask)
+{
+    return (uint16_t) pinmask_spread_32(packed, mask);
+}
 
 /**
  * Pack spread port pins using a mask
@@ -107,7 +112,12 @@ uint32_t pinmask_spread(uint32_t packed, uint32_t mask);
  * @param mask - mask of the bits we want to pack (eg. 0x8803)
  * @return - packed bits, right aligned (eg. 0b1110)
  */
-uint32_t pinmask_pack(uint32_t spread, uint32_t mask);
+uint32_t pinmask_pack_32(uint32_t spread, uint32_t mask);
+
+static inline uint16_t pinmask_pack(uint32_t spread, uint32_t mask)
+{
+    return (uint16_t) pinmask_pack_32(spread, mask);
+}
 
 /**
  * Convert spread port pin number to a packed index using a mask

units/digital_out/_dout_api.c

@@ -9,56 +9,80 @@
 #define DOUT_INTERNAL
 #include "_dout_internal.h"
 
-error_t UU_DOut_Write(Unit *unit, uint16_t packed)
+error_t UU_DOut_Spread(Unit *unit, uint16_t packed, uint16_t *spread_out)
 {
     CHECK_TYPE(unit, &UNIT_DOUT);
+    *spread_out = UU_DOut_Spread_HS(unit, packed);
+    return E_SUCCESS;
+}
 
+uint16_t UU_DOut_Spread_HS(Unit *unit, uint16_t packed)
+{
     struct priv *priv = unit->data;
     uint16_t mask = priv->pins;
-    uint16_t spread = pinmask_spread(packed, mask);
+    return pinmask_spread(packed, mask);
+}
 
+void UU_DOut_Write_HS(Unit *unit, uint16_t spread)
+{
+    struct priv *priv = unit->data;
+    uint16_t mask = priv->pins;
     uint16_t set = spread;
     uint16_t reset = ((~spread) & mask);
     priv->port->BSRR = set | (reset << 16);
-    return E_SUCCESS;
 }
 
-error_t UU_DOut_Set(Unit *unit, uint16_t packed)
+void UU_DOut_Set_HS(Unit *unit, uint16_t spread)
 {
-    CHECK_TYPE(unit, &UNIT_DOUT);
-
     struct priv *priv = unit->data;
-    uint16_t mask = priv->pins;
-    uint16_t spread = pinmask_spread(packed, mask);
-
     priv->port->BSRR = spread;
-    return E_SUCCESS;
 }
 
-error_t UU_DOut_Clear(Unit *unit, uint16_t packed)
+void UU_DOut_Clear_HS(Unit *unit, uint16_t spread)
 {
-    CHECK_TYPE(unit, &UNIT_DOUT);
-
     struct priv *priv = unit->data;
-    uint16_t mask = priv->pins;
-    uint16_t spread = pinmask_spread(packed, mask);
-
     priv->port->BSRR = (spread<<16);
-    return E_SUCCESS;
 }
 
-error_t UU_DOut_Toggle(Unit *unit, uint16_t packed)
+void UU_DOut_Toggle_HS(Unit *unit, uint16_t spread)
 {
-    CHECK_TYPE(unit, &UNIT_DOUT);
-
     struct priv *priv = unit->data;
     uint16_t mask = priv->pins;
-    uint16_t spread = pinmask_spread(packed, mask);
-
     uint16_t flipped = (uint16_t) (~priv->port->ODR) & mask;
     uint16_t set = flipped & spread;
     uint16_t reset = ((~flipped) & mask) & spread;
     priv->port->BSRR = set | (reset<<16);
+}
+
+error_t UU_DOut_Write(Unit *unit, uint16_t packed)
+{
+    CHECK_TYPE(unit, &UNIT_DOUT);
+    const uint16_t spread = UU_DOut_Spread_HS(unit, packed);
+    UU_DOut_Write_HS(unit, spread);
+    return E_SUCCESS;
+}
+
+error_t UU_DOut_Set(Unit *unit, uint16_t packed)
+{
+    CHECK_TYPE(unit, &UNIT_DOUT);
+    const uint16_t spread = UU_DOut_Spread_HS(unit, packed);
+    UU_DOut_Set_HS(unit, spread);
+    return E_SUCCESS;
+}
+
+error_t UU_DOut_Clear(Unit *unit, uint16_t packed)
+{
+    CHECK_TYPE(unit, &UNIT_DOUT);
+    const uint16_t spread = UU_DOut_Spread_HS(unit, packed);
+    UU_DOut_Clear_HS(unit, spread);
+    return E_SUCCESS;
+}
+
+error_t UU_DOut_Toggle(Unit *unit, uint16_t packed)
+{
+    CHECK_TYPE(unit, &UNIT_DOUT);
+    const uint16_t spread = UU_DOut_Spread_HS(unit, packed);
+    UU_DOut_Toggle_HS(unit, spread);
     return E_SUCCESS;
 }
 

units/digital_out/unit_dout.h

@@ -56,4 +56,17 @@ error_t UU_DOut_Toggle(Unit *unit, uint16_t packed);
  */
 error_t UU_DOut_GetPinCount(Unit *unit, uint8_t *count);
 
+// --- high-speed variants, without type checking and spreading ---
+
+/** Spread a packed word */
+error_t UU_DOut_Spread(Unit *unit, uint16_t packed, uint16_t *spread_out);
+
+// those are like the normal functions, but without driver checking and other verification (where applicable)
+// also the argument must be already spread, which saves time if the same value is used repeatedly
+uint16_t UU_DOut_Spread_HS(Unit *unit, uint16_t packed);
+void UU_DOut_Write_HS(Unit *unit, uint16_t spread);
+void UU_DOut_Set_HS(Unit *unit, uint16_t spread);
+void UU_DOut_Clear_HS(Unit *unit, uint16_t spread);
+void UU_DOut_Toggle_HS(Unit *unit, uint16_t spread);
+
 #endif //U_DOUT_H