diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..d52becb
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+*.o
+bme680
\ No newline at end of file
diff --git a/Makefile b/Makefile
index 983f8c7..4bddc80 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,5 @@
 CC=gcc
-OPT=-O2 -std=c99 -Wall -Wextra
-# OPT=-O0 -g3 -std=c99 -Wall -Wextra -pedantic
+OPT=-O2 -std=c99 -Wall -Wextra -W -pedantic
 CFLAGS=-I. $(OPT)
 CFILES=$(wildcard ./*.c)
 OBJECTS=$(patsubst %.c,%.o, $(CFILES))
diff --git a/bme680.c b/bme680.c
index 9f33840..0c92779 100644
--- a/bme680.c
+++ b/bme680.c
@@ -299,6 +299,7 @@ static int const_array1_int[16] = {
 	2147483647
 };
 
+/* long int maybe */
 static int const_array2_int[16] = {
 	4096000000, 2048000000, 1024000000, 512000000, 255744255,
 	127110228, 64000000, 32258064, 16016016, 8000000, 4000000,
@@ -529,7 +530,7 @@ int bme680_calibrate(bme680_t *bme680) {
 	bme680->cal.range_switching_error = buffer[0];
 
 	err |= read_dev(bme680, 0x02, buffer, 1);
-	bme680->cal.res_heat_range = (buffer[0] >> 4) & 0b11;
+	bme680->cal.res_heat_range = (buffer[0] >> 4) & 3;
 
 	err |= read_dev(bme680, 0x00, buffer, 1);
 	bme680->cal.res_heat_val = buffer[0];
diff --git a/bme680.h b/bme680.h
index 5d5353f..34b7456 100644
--- a/bme680.h
+++ b/bme680.h
@@ -8,7 +8,7 @@
 #define BME680_GAS_ENABLED(m) (((m >> 2) & 1) == 1) 
 
 #define BME680_IDAC(c) (c << 1)
-#define BME680_GAS_WAIT(val, scal) ((uint8_t)(((scal & 0b11) << 6) | (val & 0b111111)))
+#define BME680_GAS_WAIT(val, scal) ((uint8_t)(((scal & 3) << 6) | (val & 63)))
 
 /* connection modes */
 #define BME680_SPI   1
@@ -22,27 +22,27 @@
 #define BME680_ENABLE_GAS 4
 
 /* config values */
-#define BME680_OVERSAMPLE_X1  0b001
-#define BME680_OVERSAMPLE_X2  0b010
-#define BME680_OVERSAMPLE_X4  0b011
-#define BME680_OVERSAMPLE_X8  0b100
-#define BME680_OVERSAMPLE_X16 0b101
+#define BME680_OVERSAMPLE_X1  1
+#define BME680_OVERSAMPLE_X2  2
+#define BME680_OVERSAMPLE_X4  3
+#define BME680_OVERSAMPLE_X8  4
+#define BME680_OVERSAMPLE_X16 5
 
 /* IIR filter */
-#define BME680_IIR_COEFF_0   0b000
-#define BME680_IIR_COEFF_1   0b001
-#define BME680_IIR_COEFF_3   0b010
-#define BME680_IIR_COEFF_7   0b011
-#define BME680_IIR_COEFF_15  0b100
-#define BME680_IIR_COEFF_31  0b101
-#define BME680_IIR_COEFF_63  0b110
-#define BME680_IIR_COEFF_127 0b111
+#define BME680_IIR_COEFF_0    0
+#define BME680_IIR_COEFF_1    1
+#define BME680_IIR_COEFF_3    2
+#define BME680_IIR_COEFF_7    3
+#define BME680_IIR_COEFF_15   4
+#define BME680_IIR_COEFF_31   5
+#define BME680_IIR_COEFF_63   6
+#define BME680_IIR_COEFF_127  7
 
 /* gas related values */
-#define BME680_GAS_WAIT_X1  0b00
-#define BME680_GAS_WAIT_X4  0b01
-#define BME680_GAS_WAIT_X16 0b10
-#define BME680_GAS_WAIT_X64 0b11
+#define BME680_GAS_WAIT_X1    0
+#define BME680_GAS_WAIT_X4    1
+#define BME680_GAS_WAIT_X16   2
+#define BME680_GAS_WAIT_X64   3
 
 
 /* user supplied spi/i2c functions */