diff options
Diffstat (limited to 'src/include/gpio.h')
| -rw-r--r-- | src/include/gpio.h | 14 |
1 files changed, 5 insertions, 9 deletions
diff --git a/src/include/gpio.h b/src/include/gpio.h index af06697050..b2a341dabc 100644 --- a/src/include/gpio.h +++ b/src/include/gpio.h @@ -36,17 +36,13 @@ void gpio_output(gpio_t gpio, int value); /* * Read the value presented by the set of GPIOs, when each pin is interpreted - * as a number in 0..2 range depending on the external pullup situation. + * as a base-3 digit (LOW = 0, HIGH = 1, Z/floating = 2). + * Example: X1 = Z, X2 = 1 -> gpio_get_tristates({GPIO(X1), GPIO(X2)}) = 5 + * BASE3() from <base3.h> can generate numbers to compare the result to. * - * Depending on the third parameter, the return value is either a set of two - * bit fields, each representing one GPIO value, or a number where each GPIO is - * included multiplied by 3^gpio_num, resulting in a true tertiary value. - * - * gpio[]: pin positions to read. little-endian (less significant value first). + * gpio[]: pin positions to read. gpio[0] is less significant than gpio[1]. * num_gpio: number of pins to read. - * tertiary: 1: pins are interpreted as a quad coded tertiary. - * 0: pins are interpreted as a set of two bit fields. */ -int gpio_get_tristates(gpio_t gpio[], int num_gpio, int tertiary); +int gpio_get_tristates(gpio_t gpio[], int num_gpio); #endif /* __SRC_INCLUDE_GPIO_H__ */ |