The 20x cameras can use the 200x series F lenses, but there is no databus on the F series lenses, therefore they don't communicate the chosen f-stop to the 20x cameras, and this must be taken into consideration when using the 20x series meter. There is a way to compensate for the f-stop in the 20x cameras.
> Was the 2000 the predecessor to > the 200 range?
> Does the 2000FCM have TTL metering?
Not inherent in the camera body, but you can use a prism meter.
And vice versa, the 200x cameras can use the 20x series TCC/FE lenses, but though there is a databus on the TCC/FE series lenses, they don't communicate the chosen f-stop to the 200x cameras, because the 200x cameras do not have databus nor meter electronics to receive the message.