restructuring

2026-02-28 20:04:30 +03:00 · 2022-03-10 11:04:14 +03:00
parent 29560b7c0c
commit 733dbd75d2
1758 changed files with 14 additions and 26855 deletions
--- a/F1:F103/BMP280/dewpoint.c
+++ b/F1:F103/BMP280/dewpoint.c
@@ -0,0 +1,74 @@
+/*
+ * This file is part of the BMP280 project.
+ * Copyright 2021 Edward V. Emelianov <edward.emelianoff@gmail.com>.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "dewpoint.h"
+#include "usb.h"
+#include "proto.h"
+
+#define NKNOTS  (32)
+const uint16_t X[NKNOTS] = {1, 2, 3, 4, 5, 6, 7, 8, 10, 12, 14, 16, 19, 22, 29, 37, 47, 59, 72, 87, 104,
+                            123, 145, 171, 200, 232, 267, 348, 443, 555, 684, 832};
+const float Y[NKNOTS] = {-6.90776, -6.21461, -5.80914, -5.52146, -5.29832, -5.116, -4.96185, -4.82831,
+                         -4.60517, -4.42285, -4.2687, -4.13517, -3.96332, -3.81671, -3.54046, -3.29684,
+                         -3.05761, -2.83022, -2.63109, -2.44185, -2.26336, -2.09557, -1.93102, -1.76609,
+                         -1.60944, -1.46102, -1.32051, -1.05555, -0.814186, -0.588787, -0.379797, -0.183923};
+const float K[NKNOTS] = {0.693147, 0.405465, 0.287682, 0.223144, 0.182322, 0.154151, 0.133531, 0.111572,
+                         0.0911608, 0.0770753, 0.0667657, 0.0572834, 0.0488678, 0.0394648, 0.0304528,
+                         0.023923, 0.0189492, 0.0153176, 0.0126161, 0.010499, 0.00883123, 0.00747952,
+                         0.00634345, 0.00540186, 0.00463813, 0.00401461, 0.00327103, 0.00254071,
+                         0.00201249, 0.00162008, 0.00132348, 0.00109478};
+
+float ln(uint16_t RH){
+    // find interval
+    int idx = (NKNOTS)/2, left = 0, right = NKNOTS-1; // left, right, middle
+    while(idx > left && idx < right){
+        uint16_t midval = X[idx];
+        if(RH < midval){
+            if(idx == 0) break;
+            if(RH > X[idx-1]){ // found
+                --idx;
+                break;
+            }
+            right = idx - 1;
+            idx = (left + right)/2;
+        }else{
+            if(RH < X[idx+1]) break;  // found
+            left = idx + 1;
+            idx = (left + right)/2;
+        }
+    }
+    if(idx < 0) idx = 0;
+    else if(idx > NKNOTS-1) idx = NKNOTS - 1;
+    //USB_send("idx="); USB_send(u2str(idx)); USB_send("\n");
+    float l = Y[idx] + K[idx]*(RH - X[idx]);
+#undef NKNOTS
+    return l;
+}
+
+/**
+ * @brief dewpoint calculate dew point (*10degrC)
+ * @param T - temperature (*10degrC)
+ * @param H - rel. humidity (*10%)
+ * @return dewpoint
+ */
+int32_t dewpoint(int32_t T, uint32_t H){
+    float gamma = 17.27 * T / (2377 + T);
+    gamma += ln(H);
+    float d = 2377 * gamma / (17.27 - gamma);
+    return (int32_t)d;
+}