Improve weekly assignment exposition

content/06_electronics_design.md

@@ -27,11 +27,11 @@ Drawing the traces was more challenging. It took me a few tries before I was abl
 
 When I started milling my design, it was obviously too large. Turns out the DPI of images exported by EAGLE on retina MacBooks ends up twice as high as claimed. Luckily this is easily fixed in mods by overriding the value embedded in the png.
 
-At this point I feel like a pro at stuffing. It went by pretty quickly and I'm happy with all my joints.
+At this point I feel comfortable stuffing boards. It went by pretty quickly and I'm happy with all the joints.
 
 ### Programming
 
-It had been a few years since I've flashed a microcontroller so I was uncertain how many issues I should expect to run into. Luckily things went pretty smoothly. I encountered a few "device not found" errors that were circumvented by unplugging and replugging the programmer and boards.
+It had been a few years since I've flashed a microcontroller so I was uncertain how many issues I should expect to run into. Luckily things went pretty smoothly. I encountered a few "device not found" errors that were circumvented by unplugging and replugging the programmer and boards. I just used Neil's [echo code](http://academy.cba.mit.edu/classes/embedded_programming/hello.ftdi.44.echo.c).
 
 ![](/img/06_pcb_plus_ftdi.jpg#c)
 

content/10_input_devices.md

@@ -133,5 +133,5 @@ This board's output looks a lot better than the previous one's.
 
 ![](/img/10_better_amplification.png)
 
-I decided to plug it into my audio interface so I could listen to the output directly. It [sounds](/audio/10_bass_test.mp3) just like the untreated output of my bass.
+I decided to plug it into my (commercial) audio interface so I could listen to the output directly. It [sounds](/audio/10_bass_test.mp3) just like the untreated output of my bass.
 

content/11_output_devices.md

@@ -7,7 +7,7 @@ weight = 12
 
 Files: [midi_test.c](https://gitlab.cba.mit.edu/erik/attiny44a_blink/blob/master/midi_test.c)
 
-This week we're exploring output devices. I need to send MIDI messages for my final project, so my goal for the week is to figure out this subsystem.
+This week we're exploring output devices. I need to send MIDI messages for my final project, so my goal for the week is to figure out this subsystem. (Edit: in the end I simplified things and didn't use MIDI for my final project.)
 
 
 ### Background

content/13_interfaces.md

@@ -5,7 +5,7 @@ menu = "main"
 weight = 14
 +++
 
-Files: [embedded](https://gitlab.cba.mit.edu/erik/attiny44a_blink) (see button_serial.c) [test_app](https://gitlab.cba.mit.edu/erik/serial_cpp) [shelf_app](https://gitlab.cba.mit.edu/erik/htmaa_shelves) (see shelf_button.cpp)
+Files: [embedded](https://gitlab.cba.mit.edu/erik/attiny44a_blink) (see button_serial.c) [serial_cpp](https://gitlab.cba.mit.edu/erik/serial_cpp) [shelf_app](https://gitlab.cba.mit.edu/erik/htmaa_shelves) (see shelf_button.cpp)
 
 
 This week we're diving deeper into communication between microcontrollers and computers.