Tom's computer pages

October 30, 2023

Let's learn USB!

Start by reading my "manifesto", then continue from there if this seems interesting.

A USB Manifesto
Some recommended resources
RP2040 versus the STM32F103
"Official" USB variable names
Maple boards, resistors, and such
Black Pill (STM32F411)
Papoon - a first look
TinyUSB (for the STM32F103)
Olimexino-STM32
Papoon - a second look
Papoon - a look inside
Interrupts and the STM32F103
Papoon with interrupts
Enumeration - Papoon as a case study
Endpoints
Delays
Frames
ttyACM or ttyUSB?
ACM specification
Send and Receive
Enumeration revisited
Regbits (papoon)
Wireshark and USB
CP2102 enumeration, wireshark
F103 enumeration in detail
A bug!? -- the "56" bug
OpenOCD
use a real Maple board
Baboon - working towards an all C driver
Progress Report - 11-28-2023
Wireshark - more and better
Set Address is special!
More about ACM
stm32f103_usb from Daedalean
When will we run out of RAM?
Progress Report - 12-2-2023
Linker tricks
Endpoint registers
Races an interrupts
CP2102 fakery
CP2102 resources

I said I wasn't going to do this, but along the way I decided to roll up my sleeves and dive in, putting together a C++ primer. This was part of my effort to understand the "papoon" code, which ultimately served as just a stepping stone. I was not convinced to begin using C++ for this or any other embedded project.

C++ basics
C++ classes - part 1
C++ classes - part 2
C++ templates

And for a rainy day. A preview of USB in the STM32F411 (black pill). This chip has a USB subsystem that is entirely different fom the F103.

USB in the Black Pill

Feedback? Questions? Drop me a line!

Tom's Computer Info / [email protected]