bare7_3

examples/bare7.rs

@@ -34,7 +34,7 @@ fn main() -> ! {
     let rcc = p.RCC;
 
     // Output MCO2 to PC9 as SYSCLK/4:
-    rcc.cfgr.modify(|_, w| w.mco2().sysclk().mco2pre().div4());
+    rcc.cfgr.modify(|_, w| w.mco2().sysclk().mco2pre().div1());
 
     // Enable GPIOC:
     rcc.ahb1enr.modify(|_, w| w.gpiocen().enabled());
@@ -42,7 +42,7 @@ fn main() -> ! {
 
     // Set Port C pin 9 to alternate function MCO2.
     gpioc.moder.modify(|_, w| w.moder9().alternate());
-    gpioc.ospeedr.modify(|_, w| w.ospeedr9().very_high_speed());
+    gpioc.ospeedr.modify(|_, w| w.ospeedr9().low_speed());
 
     // Now lock the clocks:
     let rcc = rcc.constrain();
@@ -175,17 +175,21 @@ fn main() -> ! {
 //
 // 3. Now reprogram the PC9 to be "Low Speed", and re-run at 84Mz.
 //
-//    Did the frequency change in comparison to assignment 5?
+//    Did the frequency change in comparison to assignment 5? << Assuming last task
 //
-//    ** your answer here **
+//    ** The frequency is the same. BUT, changing the divider from 4 to 1, meaning
+//    that MCO2 = SYSCLK = 84 MHz, the output is zero, while it is not zero with
+//    "very_high_speed()" on. **
 //
 //    What is the peak to peak reading of the signal (and why did it change)?
 //
-//    ** your answer here **
+//    ** Zero at MCO2 = 84 MHz and low_speed mode. 3.95 V at MCO = 21 MHz. **
 //
 //    Make a screen dump or photo of the oscilloscope output.
 //    Save the the picture as "bare_6_84mhz_low_speed".
 //
+//    ** It is the MCO2 = 84 MHz, low_speed mode I put in the pictures/ folder. **
+//
 //    Commit your answers (bare7_3)
 //
 // 4. Revisit the `README.md` regarding serial communication.