pimoroni-pico/drivers/analogmux/analogmux.cpp

91 lines
2.2 KiB
C++

#include "analogmux.hpp"
#include <cstdio>
namespace pimoroni {
AnalogMux::AnalogMux(uint addr0_pin, uint addr1_pin, uint addr2_pin,
uint en_pin, uint muxed_pin)
: addr0_pin(addr0_pin), addr1_pin(addr1_pin), addr2_pin(addr2_pin)
, en_pin(en_pin), muxed_pin(muxed_pin), pull_ups(0), pull_downs(0) {
gpio_init(addr0_pin);
gpio_set_dir(addr0_pin, GPIO_OUT);
max_address = 0b001;
if(addr1_pin != PIN_UNUSED) {
gpio_init(addr1_pin);
gpio_set_dir(addr1_pin, GPIO_OUT);
max_address = 0b011;
if(addr2_pin != PIN_UNUSED) {
gpio_init(addr2_pin);
gpio_set_dir(addr2_pin, GPIO_OUT);
max_address = 0b111;
}
}
if(en_pin != PIN_UNUSED) {
gpio_init(en_pin);
gpio_set_dir(en_pin, GPIO_OUT);
}
if(muxed_pin != PIN_UNUSED) {
gpio_set_input_enabled(muxed_pin, true);
}
}
void AnalogMux::select(uint8_t address) {
if(address <= max_address) {
bool to_pull_up = (pull_ups & (1u << address));
bool to_pull_down = (pull_downs & (1u << address));
if((muxed_pin != PIN_UNUSED) && !(to_pull_up || to_pull_down)) {
gpio_disable_pulls(muxed_pin);
}
gpio_put(addr0_pin, address & 0b001);
if(addr1_pin != PIN_UNUSED) {
gpio_put(addr1_pin, address & 0b010);
}
if(addr2_pin != PIN_UNUSED) {
gpio_put(addr2_pin, address & 0b100);
}
if(en_pin != PIN_UNUSED) {
gpio_put(en_pin, true);
}
if((muxed_pin != PIN_UNUSED) && (to_pull_up || to_pull_down)) {
gpio_set_pulls(muxed_pin, to_pull_up, to_pull_down);
}
sleep_us(10); // Add a delay to let the pins settle before taking a reading
}
}
void AnalogMux::disable() {
if(en_pin != PIN_UNUSED) {
gpio_put(en_pin, false);
}
}
void AnalogMux::configure_pulls(uint8_t address, bool pullup, bool pulldown) {
if(address <= max_address) {
if(pullup)
pull_ups |= (1u << address);
else
pull_ups &= ~(1u << address);
if(pulldown)
pull_downs |= (1u << address);
else
pull_downs &= ~(1u << address);
}
}
bool AnalogMux::read() {
if(muxed_pin != PIN_UNUSED) {
return gpio_get(muxed_pin);
}
return false;
}
}