extern crate stm32f103xx;
use ::i2c::{I2C, TransDir, DutyType};
const DS3231_ADDR: u8 = 0b1101000;
const DS3231_REG_SEC: u8 = 0x00;
const DS3231_REG_CTL: u8 = 0x0e;
pub struct DS3231<'a> {
i2c: I2C<'a>
}
pub struct Date {
pub second: u8,
pub minute: u8,
pub hour: u8,
pub day: u8,
pub date: u8,
pub month: u8,
pub year: u8,
pub am: bool,
pub am_enabled: bool
}
impl<'a> DS3231<'a> {
pub fn new(i2c_reg: &'a stm32f103xx::i2c1::RegisterBlock,
rcc_reg: &'a stm32f103xx::rcc::RegisterBlock) -> DS3231<'a> {
DS3231{i2c: I2C::new(i2c_reg, rcc_reg)}
}
fn bcd2dec(bcd: u8) -> u8 {
(bcd >> 4) * 10 + (bcd & 0x0f)
}
fn dec2bcd(dec: u8) -> u8 {
((dec / 10) << 4) | (dec % 10)
}
pub fn init(&self) {
let i2c = &self.i2c;
i2c.init(0x01, 400_000, DutyType::DUTY1);
i2c.start(true, true);
i2c.send_addr(DS3231_ADDR, TransDir::TRANSMITTER, true);
i2c.send(DS3231_REG_CTL, true);
i2c.send(0x00, true);
i2c.send(0x00, true);
i2c.stop(true);
}
pub fn read_fulldate(&self) -> Date {
let mut buf: [u8; 7] = [0; 7];
let i2c = &self.i2c;
i2c.conf_ack(true); /* enable ack */
i2c.start(true, true); /* start condition (for writing reg addr) */
i2c.send_addr(DS3231_ADDR, TransDir::TRANSMITTER, true);
i2c.send(DS3231_REG_SEC, true);
/* restart condition (for reading val from the reg addr) */
i2c.start(true, true);
i2c.send_addr(DS3231_ADDR, TransDir::RECEIVER, true);
for i in 0..6 {
buf[i] = i2c.recv(true);
}
i2c.conf_ack(false); /* disable ack (send nack) */
buf[6] = i2c.recv(true);
i2c.stop(true);
let am_enabled = (buf[2] >> 6) & 1 == 1;
let hour = if am_enabled {
(buf[2] & 0x0f) + ((buf[2] >> 4) & 1) * 10
} else {
DS3231::bcd2dec(buf[2])
};
let am = if am_enabled {(buf[2] >> 5) & 1 == 0} else {hour < 12};
Date{second: DS3231::bcd2dec(buf[0]),
minute: DS3231::bcd2dec(buf[1]),
hour: hour,
day: DS3231::bcd2dec(buf[3]),
date: DS3231::bcd2dec(buf[4]),
month: DS3231::bcd2dec(buf[5]),
year: DS3231::bcd2dec(buf[6]),
am: am,
am_enabled: am_enabled}
}
pub fn write_fulldate(&self, date: &Date) {
let i2c = &self.i2c;
let hour = if date.am_enabled {
(1 << 6) | ((if date.am {0} else {1}) << 5) |
((date.hour / 10) << 4) | (date.hour % 10)
} else {
DS3231::dec2bcd(date.hour)
};
let buf: [u8; 7] = [DS3231::dec2bcd(date.second),
DS3231::dec2bcd(date.minute),
hour,
DS3231::dec2bcd(date.day),
DS3231::dec2bcd(date.date),
DS3231::dec2bcd(date.month),
DS3231::dec2bcd(date.year)];
i2c.conf_ack(true);
i2c.start(true, true); /* start condition for writing */
i2c.send_addr(DS3231_ADDR, TransDir::TRANSMITTER, true);
i2c.send(DS3231_REG_SEC, true);
for i in 0..7 {
i2c.send(buf[i], true);
}
i2c.stop(true);
}
}