I was playing with the Teensy 3.6 some more last night and got it waiting & responding to commands by serial (the built-in ftdi usb-serial not via max232 yet), reading/writing to files in a fat32 fs on the sd, blinking the on-board led during drive activity, and displaying text on a tiny 128x64 0.96 inch oled display via i2c.
All while sitting at a counter at a diner. Because it didn't need anything but a laptop, usb cable, and the chip stuck on the end of the cable, and 4 jumper wires just for the oled display which was just for play anyway, probably wouldn't actually want that on the finished device. These arduino libraries and built in examples make it all pretty easy to get started. And teensy has an rtc built-in too. Needs another battery, but a cr2032 can apparantly keep the rtc going for about 17 years, so, not a problem. This 32 bit 180mhz cpu is overkill, but it's just handy having the sd card reader and usb port already built in. The cpu can be underclocked in software but I don't know if it goes all the way down to 4! On Fri, Aug 24, 2018, 11:28 AM Fugu ME100 <b4me...@hotmail.com> wrote: > At least for an ATMEL MEGA not much power at all especially if it is run > at 4MHz. The biggest rated current draw on the TPDD emulator is the SD > card which is spec’d at around 100mA while writing to the flash, but is a > little manufacturer dependent some are better than others. The TPDD > emulator can also be put to sleep when idle which reduces the overall power > drain to the uA region or lower depending on the sleep level. So with a > single no name AA and taking into account inefficiencies in the power > supply chain you could theoretically run the system continuously for about > 10 hours. By sleeping the MEGA/TPDD when it was not being used that time > could extend out to days if not weeks. The sleep is also useful if you > forget to switch off the board when done :) > > I am sure the other processors could also be put to sleep if the right > hardware/pins were connected. The latest generation of embedded MCUs have > really low sleep currents if the board is built correctly, however most are > poorly designed leading to high leakage currents. > > As to the powerful CPU question in its day the DVI box ran a 4MHz Z80A > compatible so could easily outperform the model T - IMHO :) A 4MHz Mega > seems quite in keeping with the original DVI, especially when it is the > size of a AA battery…… >
