bare7_2

examples/bare7.rs

@@ -33,8 +33,8 @@ fn main() -> ! {
     let rcc = p.RCC.constrain();
 
     // 16 MHz (default, all clocks)
-    let clocks = rcc.cfgr.freeze();
-
+    // let clocks = rcc.cfgr.freeze();
+    let clocks = rcc.cfgr.sysclk(84.mhz()).pclk1(42.mhz()).pclk2(84.mhz()).freeze();
     let gpioa = p.GPIOA.split();
 
     let tx = gpioa.pa2.into_alternate_af7();
@@ -49,6 +49,12 @@ fn main() -> ! {
     )
     .unwrap();
 
+    let gpioc = p.GPIOC.split();
+    gpioc.pc9.into_alternate_af0().set_speed(hal::gpio::Speed::VeryHigh);
+    // MCO_2 alternate function AF0, STM32F401xD STM32F401xE data sheet
+    // table 9
+    // AF0, gpioc reset value = AF0
+
     // Separate out the sender and receiver of the serial port
     let (mut tx, mut rx) = serial.split();
 
@@ -144,15 +150,15 @@ fn main() -> ! {
 //
 //    What is the frequency of MCO2 read by the oscilloscope.
 //
-//    ** your answer here **
+//    ** 84MHz **
 //
 //    Compute the value of SYSCLK based on the oscilloscope reading.
 //
-//    ** your answer here **
+//    ** 84MHz **
 //
 //    What is the peak to peak reading of the signal.
 //
-//    ** your answer here **
+//    ** 9.8V **
 //
 //    Make a screen dump or photo of the oscilloscope output.
 //    Save the the picture as "bare_6_84mhz_high_speed"