From: Jan "Yenya" Kasprzak Date: Sat, 15 Dec 2012 21:21:25 +0000 (+0100) Subject: ambient.c: ambient light hysteresis X-Git-Url: https://www.fi.muni.cz/~kas/git//home/kas/public_html/git/?a=commitdiff_plain;h=20177f823fc0effcc9c5c389a629294c5ed367a1;p=bike-lights.git ambient.c: ambient light hysteresis --- diff --git a/firmware/ambient.c b/firmware/ambient.c index 025b0c4..c6c6a65 100644 --- a/firmware/ambient.c +++ b/firmware/ambient.c @@ -4,49 +4,64 @@ static uint16_t ambient_val; volatile unsigned char ambient_zone; -static unsigned char ambient_zone_set; -static uint16_t ambient_zones[] = { - 0x0c00, 0x0d00, 0x1000, 0x1800, 0x2800, 0x2f80, 0xffff +/* My photodiode reads 0x00C5 .. 0x033B */ +typedef struct { + uint16_t lo, hi; +} ambient_zone_t; + +/* + * Note: these have to be sorted, starting with 0, ending with 0xFFFF + * and having small overlaps in order to provide a bit of hysteresis. + */ +static ambient_zone_t ambient_zones[] = { + { 0x0000, 0x3120 }, // dark + { 0x30f0, 0x5000 }, + { 0x4c00, 0x8000 }, + { 0x7800, 0xffff } }; #define N_AMBIENT_ZONES (sizeof(ambient_zones)/sizeof(ambient_zones[0])) void init_ambient() { ambient_val = 0; - ambient_zone = 0; - ambient_zone_set = 0; + ambient_zone = 1; } void ambient_zone_changed() { +#if 1 log_byte(0xab); log_byte(ambient_zone); log_word(ambient_val); log_flush(); +#endif - pattern_reload(); + // led_set_pattern(N_PWMLEDS, status_led_pattern_select()); + // led_set_pattern(N_PWMLEDS+1, illumination_led_pattern_select()); + // pattern_reload(); } void ambient_adc(uint16_t adcval) { - unsigned char newzone; - - if (!ambient_zone_set) - ambient_val = adcval << 4; - else // running sum - ambient_val += adcval - (ambient_val >> 4); - - newzone = 0; - while (newzone < N_AMBIENT_ZONES-1 - && ambient_zones[newzone] < ambient_val) - newzone++; - - // TODO: implement hysteresis? - if (!ambient_zone_set || newzone != ambient_zone) { - ambient_zone = newzone; - ambient_zone_set = 1; - // ambient_zone_changed(); + unsigned char old_zone = ambient_zone; + + ambient_val += adcval - (ambient_val >> 6); + + while (ambient_zones[ambient_zone].lo > ambient_val) + ambient_zone--; + + while (ambient_zones[ambient_zone].hi < ambient_val) + ambient_zone++; + +#if 0 + if (old_zone != ambient_zone) { + log_byte(0xab); + log_byte(ambient_zone); + log_word(adcval); + log_flush(); } + // ambient_zone_changed(); +#endif }