What money is being exchanged here? In this sentence:


  他换了1，000美元。


Did he use dollars to exchange for another money or did he use another money and got dollars as a result?

EDIT:
What about:


  他换了1，000美元的人民币。
“他换了1，000美元” is not clear; which denomination became what?

他用人民币换了1，000美元。（He changed RMB, bought $ 1000)

他把1000美元换成了人民币。（He changed $ 1000, bought RMB)