I’ve always been curious why there’s no generic USB serial chip. It seems like the most obvious thing in the world. I’ve noticed ESP32 boards tend to come with one of two proprietary chips, with their own drivers. Do you know why this isn’t all standard?
As someone mentioned elsewhere in the thread, the USB CDC drivers (the closest thing to a "generic USB serial" interface) on Windows were buggy for a very long time, so vendors avoided it. It'd be feasible to make one now, but there's no compelling reason for vendors to change, either.
The generic CDC class does not support high-speed bit-bang JTAG modes. Most ESP32 chips have a built in boot-loader for normal 3.3v UART protocols.
Retro computer eMMC memory-recovery hardware like the xgecu T76 is a USB3.0 device with built in FPGA and gpio voltage-level-shifters. It may eventually solve a lot of the hobby diagnostic/recovery tool issues, but the Beta software is currently Windows only. There is a FOSS project that should port to Linux and MacOS systems soon:
Keep in mind, the software is still being built, but I'd keep an eye open for full-speed JTAG support releases in the next year or so. YMMV Best regards =3
minipro already runs on macOS and Linux. There's better tools out there for general-purpose IO, though - the Glasgow Explorer [1] is probably best in class, for instance. (Although one place where MiniPro-type devices outperform it is in interacting with old EEPROMs which require >5V Vpp.)
