If I'm not seriously mistaken, a typical T1-3/4 LED, red, uses about 20mA when operating on a 100% duty cycle (or...just on). I don't have it immediately available but if I'm recalling correctly green, blue and especially white require more to reach full brightness. Now the LEDs used in 1989 were not particularly bright, and were probably not driven at full power either, but I couldn't help but notice that 1mA is probably barely enough to forward-bias the LED.
You are mostly correct. I would not say an LED uses 20mA, but that it tolerates that current. It emits light with far less current, but as you've mentioned, a 1989 LED is less efficient than what is available today. The LED code was overhauled for v0.8.0. Maximum external LED drive is 3.3v through a 220 Ohm resistor at 9.7% duty cycle.
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