test of i2c->spi wip1

examples/rtt_rtic_i2c.rs

+//! cargo run --examples rtt-pwm
+
+#![deny(unsafe_code)]
+// #![deny(warnings)]
+#![no_main]
+#![no_std]
+
+use panic_halt as _;
+use rtt_target::{rprintln, rtt_init_print};
+
+use stm32f4xx_hal::{
+    gpio::{
+        gpiob::{PB8, PB9},
+        gpioc::PC13,
+        AlternateOD, Edge, ExtiPin, Input, PullUp, Speed, AF4,
+    },
+    i2c::I2c,
+    prelude::*,
+    stm32::I2C1,
+};
+
+#[rtic::app(device = stm32f4xx_hal::stm32, peripherals = true)]
+const APP: () = {
+    #[init]
+    fn init(cx: init::Context) {
+        rtt_init_print!();
+        rprintln!("init");
+        let dp = cx.device;
+
+        // Set up the system clock, 48MHz
+        let rcc = dp.RCC.constrain();
+        // let clocks = rcc.cfgr.sysclk(48.mhz()).freeze();
+        let clocks = rcc.cfgr.freeze();
+        // let clocks = rcc
+        //     .cfgr
+        //     .hclk(48.mhz())
+        //     .sysclk(48.mhz())
+        //     .pclk1(24.mhz())
+        //     .pclk2(24.mhz())
+        //     .freeze();
+
+        // Set up I2C.
+        let gpiob = dp.GPIOB.split();
+        let scl = gpiob.pb8.into_alternate_af4().set_open_drain();
+        let sda = gpiob.pb9.into_alternate_af4().set_open_drain();
+        let mut i2c = I2c::i2c1(dp.I2C1, (scl, sda), 400.khz(), clocks);
+
+        rprintln!("here");
+
+        // configure
+        // 7:6 -     reserved
+        // 5   ORDER logic 0, the MSB of the data word is transmitted first.
+        //           logic 1, the LSB of the data word is transmitted first.
+        // 4   -     reserved
+        // 3:3 M1:M0 Mode selection
+        //           00 - SPICLK LOW when idle; data clocked in on leading edge (CPOL = 0, CPHA = 0)
+        //           01 - SPICLK LOW when idle; data clocked in on trailing edge (CPOL = 0, CPHA = 1)
+        //           10 - SPICLK HIGH when idle; data clocked in on trailing edge (CPOL = 1, CPHA = 0)
+        //           11 - SPICLK HIGH when idle; data clocked in on leading edge (CPOL = 1, CPHA = 1)
+        // 1:0 F1:F0 SPI clock rate
+        //           00 - 1843 kHz
+        //           01 - 461 kHz
+        //           10 - 115 kHz
+        //           11 - 58 kHz
+
+        let i2c_addr = 0x50 >> 1;
+        let i2c_command_conf = 0xF0;
+
+        let i2c_conf_reg = (0b0 << 5) /* MSB First */ |
+                           (0b10 << 2) /* Mode 3 */ |
+                           (0b00 << 0) /* 1843 kHz */;
+
+        let x = i2c.write(i2c_addr, &[i2c_command_conf, i2c_conf_reg]);
+        rprintln!("configure {:?}", x);
+
+        // write to spi with CS0 (command 01..0f)
+        let i2c_command_cs0 = 0x01; // bit 0 set
+        loop {
+            let x = i2c.write(i2c_addr, &[i2c_command_cs0, 0x00, 0xFF, 0xFF, 0xFF]);
+            rprintln!("data {:?}", x);
+        }
+    }
+
+    #[idle]
+    fn idle(_cx: idle::Context) -> ! {
+        rprintln!("idle");
+        loop {
+            continue;
+        }
+    }
+};