diff --git a/bme680.c b/bme680.c
index d102676..0e833d3 100644
--- a/bme680.c
+++ b/bme680.c
@@ -83,6 +83,8 @@ int bme680_init(bme680_t *bme680, uint8_t mode) {
 
 	bme680->mode = mode;
 	bme680->spi_page = 0; 
+	bme680->gas_valid = 0;
+	bme680->heat_stab = 0;
 
 	if (bme680->dev.init() != 0) {
 		return 1;
@@ -177,10 +179,6 @@ int bme680_configure(bme680_t *bme680) {
 	err |= write_dev(bme680, REG_CTRL_GAS_1, ctrl_gas1);
 	err |= write_dev(bme680, REG_CTRL_GAS_0, ctrl_gas0);
 
-	// TODO: check gas_valid_r and heat_stab_r in 0x2B
-
-
-
 SKIP_GAS:
 	return err;
 }
@@ -249,12 +247,21 @@ int bme680_read(bme680_t *bme680) {
 	}
 
 	/* read gas adc ?*/
+	// TODO: read 2 bytes once
 	if (BME680_GAS_ENABLED(bme680->mode)) {
 		err |= read_dev(bme680, 0x2A, buffer, 2);
 		bme680->adc.gas = (buffer[0] << 2) | (buffer[1] >> 6);
 
 		err |= read_dev(bme680, 0x2B, buffer, 1);
 		bme680->adc.gas_range = buffer[0] & 0xF;
+
+		/* check gas validity status (if one actually took place ??? ) */
+		err |= read_dev(bme680, 0x2B, buffer, 1);
+		bme680->gas_valid = (buffer[0] >> 5) & 1 ;
+
+		/* check heater stability. if it managed to get to temp within given time + preload current */
+		err |= read_dev(bme680, 0x2B, buffer, 1);
+		bme680->heat_stab = (buffer[0] >> 4) & 1;
 	}
 
 	/* read/convert in order ..*/
diff --git a/bme680.h b/bme680.h
index 0ff82db..9fb5389 100644
--- a/bme680.h
+++ b/bme680.h
@@ -135,6 +135,8 @@ struct bme680 {
 	struct bme680_adc adc;
 	uint8_t mode;
 	uint8_t spi_page; 
+	uint8_t gas_valid;
+	uint8_t heat_stab;
 };
 
 typedef struct bme680 bme680_t;
diff --git a/main.c b/main.c
index fcb3143..21bd8c0 100644
--- a/main.c
+++ b/main.c
@@ -76,9 +76,9 @@ int main(void) {
 
 		/* define the time between the start of heating and start of resistance sensing in this s.p.*/
 		/* Bosch datasheet suggests ~30 - 40ms is usually all that is required to get up to temp. */
-		/* 50 * X4 = 200 ms wait before sampling resistance starts. */
+		/* 25 * X4 = 100 ms wait before sampling resistance starts. */
 		/* the first value is 6-bit (0...64) with 1 ms step size. */
-		bme680.cfg.gas_wait[i] = BME680_GAS_WAIT(50, BME680_GAS_WAIT_X4);
+		bme680.cfg.gas_wait[i] = BME680_GAS_WAIT(25, BME680_GAS_WAIT_X4);
 	}
 
 	/* The BME680 does not cycle between setpoints. They have to be manually set. */
@@ -140,6 +140,12 @@ int main(void) {
 		}
 	}
 
+	/* print out heat stability and gas valid flags. should both be 1 !! */
+	if (BME680_GAS_ENABLED(bme680.mode)) {
+		printf("=== gas_valid_r: %d\n", bme680.gas_valid);
+		printf("=== heat_stab_r: %d\n", bme680.heat_stab);
+	}
+
 	bme680_deinit(&bme680);
 
 	return 0;