From 714ace54837d4c89406a358a75361080a9455e93 Mon Sep 17 00:00:00 2001
From: Martin Mares <mj@ucw.cz>
Date: Fri, 14 Jul 2023 19:07:05 +0200
Subject: [PATCH] test-sinclair: RC again, this time with the correct checksum

---
 test-sinclair/main.c | 108 ++++++++++++++++++-------------------------
 1 file changed, 46 insertions(+), 62 deletions(-)

diff --git a/test-sinclair/main.c b/test-sinclair/main.c
index 5e90ecf..fc8a370 100644
--- a/test-sinclair/main.c
+++ b/test-sinclair/main.c
@@ -302,66 +302,38 @@ static void tm_show(void)
 
 /*** Infra-red remote control simulator ***/
 
+/*
+ *  The AC unit expects demodulated IR signal. The RC sends 52-bit messages
+ *  (plus leader and trailer). The last 4 bits are a complement of checksum
+ *  of 4-bit nibbles.
+ */
+
 #define RC_POWER_OFF_HI		0b00000000000000000000
 #define RC_POWER_OFF_LO		0b00000000000000010000000010100100
 
 #define RC_DEFAULT_HI		0b00000011000000000000
 
-// Various temperatures
-#define RC_17_COOL_AUTO		0b00000000000000010000000000101001
-#define RC_18_COOL_AUTO		0b00000000000000010000000000111000
-#define RC_19_COOL_AUTO		0b00000000000000010000000001000111
-#define RC_20_COOL_AUTO		0b00000000000000010000000001010110
-#define RC_21_COOL_AUTO		0b00000000000000010000000001100101
-#define RC_22_COOL_AUTO		0b00000000000000010000000001110100
-#define RC_23_COOL_AUTO		0b00000000000000010000000010000011
-#define RC_24_COOL_AUTO		0b00000000000000010000000010010010
-#define RC_25_COOL_AUTO		0b00000000000000010000000010100001
-#define RC_26_COOL_AUTO		0b00000000000000010000000010110000
-#define RC_27_COOL_AUTO		0b00000000000000010000000011001111
-#define RC_28_COOL_AUTO		0b00000000000000010000000011011110
-#define RC_29_COOL_AUTO		0b00000000000000010000000011101101
-#define RC_30_COOL_AUTO		0b00000000000000010000000011111100
-
-// Various fan settings
-#define RC_17_COOL_HI		0b00000000000000010000100000100001
-#define RC_17_COOL_MED		0b00000000000000010001000100100111
-#define RC_17_COOL_LO		0b00000000000000010010001000100101
-
-// Stand-alone, no temperature nor fan setting
-#define RC_DEHUMIDIFY		0b00000000000000010010010000100011
-
-// Combines with a temperature setting, but no fan setting
-#define RC_17_WARM		0b00000000000000010000001100100110
-
-// All modes have a sleep variant, which we do not use yet
-#define RC_17_COOL_AUTO_SLEEP	0b00000000000010010000000000100001
-
-static const u32 rc_fan_settings[4] = {
-	0,
-	RC_17_COOL_LO ^ RC_17_COOL_AUTO,
-	RC_17_COOL_MED ^ RC_17_COOL_AUTO,
-	RC_17_COOL_HI ^ RC_17_COOL_AUTO,
+// Combines with a temperature setting (17-30)
+#define RC_COOL_AUTO		0b00000000000000010000000000000000
+#define RC_COOL_HI		0b00000000000000010000100000000000
+#define RC_COOL_MED		0b00000000000000010001000100000000
+#define RC_COOL_LO		0b00000000000000010010001000000000
+
+static const u32 rc_cool_fan[4] = {
+	RC_COOL_AUTO,
+	RC_COOL_LO,
+	RC_COOL_MED,
+	RC_COOL_HI,
 };
 
-static const u32 rc_temp_settings[14] = {
-#define X(t) RC_##t##_COOL_AUTO ^ RC_17_COOL_AUTO
-	X(17),
-	X(18),
-	X(19),
-	X(20),
-	X(21),
-	X(22),
-	X(23),
-	X(24),
-	X(25),
-	X(26),
-	X(27),
-	X(28),
-	X(29),
-	X(30),
-#undef X
-};
+// Combines with a temperature setting (15-25)
+#define RC_WARM			0b00000000000000010000001100000000
+
+// This is sent with temperature=17
+#define RC_DEHUMIDIFY		0b00000000000000010010010000000000
+
+// This can be added to any command to enable sleep mode, but we do not issue these yet
+#define RC_SLEEP		0b00000000000010000000000000000000
 
 enum rc_mode {
 	MODE_OFF,
@@ -372,7 +344,7 @@ enum rc_mode {
 
 static byte rc_mode = MODE_COOL;	// MODE_xxx
 static byte rc_fan;			// 0-3
-static byte rc_temp = 17;		// 17-30
+static byte rc_temp = 17;		// 15-30
 
 static void rc_init(void)
 {
@@ -398,22 +370,34 @@ static void rc_encode(void)
 	}
 
 	rc_pattern[0] = RC_DEFAULT_HI;
-	uint t = rc_temp, f = rc_fan;
+	uint t = rc_temp;
 
 	if (rc_mode == MODE_COOL) {
-		rc_pattern[1] = RC_17_COOL_AUTO;
+		rc_pattern[1] = rc_cool_fan[rc_fan];
+		if (t < 17)
+			t = 17;
+		if (t > 30)
+			t = 30;
 	} else if (rc_mode == MODE_WARM) {
-		rc_pattern[1] = RC_17_WARM;
-		f = 0;
+		rc_pattern[1] = RC_WARM;
+		if (t < 15)
+			t = 15;
+		if (t > 25)
+			t = 25;
 	} else {
 		rc_pattern[1] = RC_DEHUMIDIFY;
-		f = t = 0;
+		t = 17;
 	}
 
-	rc_pattern[1] ^= rc_fan_settings[f];
+	// Encode temperature
+	rc_pattern[1] |= (t - 15) << 4;
 
-	if (t >= 17 && t < 17 + ARRAY_SIZE(rc_temp_settings))
-		rc_pattern[1] ^= rc_temp_settings[t - 17];
+	// Compute checksum
+	uint sum = 0;
+	for (uint i=0; i<2; i++)
+		for (uint j=0; j<32; j+=4)
+			sum += (rc_pattern[i] >> j) & 0x0f;
+	rc_pattern[1] |= (sum & 0x0f) ^ 0x0f;
 }
 
 void tim4_isr(void)
-- 
2.39.2