There are lots of very expensive industrial instruments that are stuck with serial interfaces. Perhaps EVs follow the same thinking - manufacturers of very high end equipment can be very conservative. They go with what they think is old reliable/proven technology for interfaces, none of this fancy USB stuff even though it’s been around for decades.
With no native serial interfaces in laptops anymore it can make things difficult. I’ve long since abandoned Prolific USB-to-serial chips, they’re awful. Fortunately FTDI are much better, but there are still some pieces of equipment that are cranky with converters.
the … well, the BIOS could be set so it will … no.
It will need to actively detect the type of cards currently inserted, and listen to (because it’s the host) the power card when the button on the power card is depressed. It will then send some bytes over to tell it to turn on, say, 4 LEDs.
And because of we are actually using USB instead of hard-wiring one, we need to do USB handshake and initialization.
That sound like so much work compared to something that used to live on the battery itself. So you only need maybe 50 extra transistors on the battery controller. Yes, not having it on the battery IC still adds this communication, but this can be done hardware (e.g. below even the BIOS layer and in the power management layer), which might be only a few hundred transistors or maybe 50 lines of code)
Not quite sure I understand your reply. I am simply saying I know I got a USB to serial connection to work in one instance. I used the USB to serial converter on the arduino mega board, connected to the ATmega1280’s UART0 pins (TXD0 and RXD0), which was in turn connected to this TTL to RS-232 logic level converter from sparkfun via the ATmega1280’s UART1 pins (TXD1 and RXD1) which was connected to the device with the RS-232 port. However, my project did other things so it needed the Arduino for that, just a converter would not need an extra micro controller. Hence this is not the optimal solution but I know it worked so integrating all these components onto one board should also work.
Also, I don’t believe this would depend on the BIOS. It depends on the arduino USB to serial drivers that arduino maintains. So, if Arduino mega works on framework, this idea should also work on framework. Since this is just an adapter, presumably removing the ATmega1280 and just connecting the Sparkfun TTL level converter to USB to serial chip from the mega would work too.
I also found this which uses " FTDI FT232 paired with a Zywyn ZT213 RS232 Transceiver" so putting these on one board might work too and would be a better design. This would depend on FTDI drivers, presumably.
Yes, much better than Prolific drivers. There has been so much counterfeiting of the Prolific chips that the drivers end up blacklisting legitimate chips and rendering them non-functional. Much easier to go with FTDI who don’t have this issue and keep their drivers up to date too.
I was replying to a comment suggesting a battery level indicator expansion card and explaining why it is basically impossible
I’m not saying a USB to RS232 is undoable. It is perfectly doable. Whether the RS232 can fit comfortable onto one, however, I do not think so.
There are also serial ports that are hard-wired to motherboard resources (perhaps to the chipset). Exactly how that works, I do not know. But there are things called “hardware serial” that are much faster (and much lower latency)
@Brenton_Ferullo
Search for Magsafe - there are a lot of conversations about the topic and at least two people here who have done it. One is a very nice design.
Just some random ideas. Sorry if some of these were mentioned before already (I haven’t read all posts in detail):
Arduino-like chip with some leds and gpio pins
Wireless game controller with small battery
Thinkpad-like mouse nipple with actual left- and right mouse buttons. (for whatever reason the designers of the Framework forgot the mouse buttons around the touchpad).
