Modeling 8266 GPIOs in LTSpice?

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Joined May 29, 2021
I'm trying to model some external circuitry with GPIO pins on an esp8266ex. There are a few scenarios I care about, and I wanted to get some input on if I'm doing this right:

# The input case
On generic GPIOs configured as INPUT are in a high impedence state. What I've read on the internet is that is modeled as say a 10Meg resistor to ground, so that would be like picture 1679429211751.png.

# The pins I'm unsure of case
Then there are pins I'm unclear if they are high impedence or not like GPIO 0 or EN during boot. In the data sheets these are shown as something like 1679429623645.png but in LTSpice there is no actual ground connection here which makes me wonder if I'm modeling that right. It shows GPIO 0 as 3.3V which I expect, but when I ask for the current flowing over R12 it shows 0. That's expected with no ground, but in practice I think it likely is actually flowing some power which tells me I'm modeling this wrong.

How would you model these GPIOs more accurately in LTSPice?
How can you tell what the state of a circuit is in terms of its impedance or resistance to ground if you physically had one in front of you?