https://en.bitcoin.it/wiki/Wallet_import_format

Trying to follow this example here to do this in PHP, but I get stuck at step 3.

I can't seem to get the same SHA256 hash.

I take the extended key from step 2 "800C28FCA386C7A227600B2FE50B7CAE11EC86D3BF1FBE471BE89827E19D72AA1D"

and SHA256 it.

I should get "8147786C4D15106333BF278D71DADAF1079EF2D2440A4DDE37D747DED5403592" according to step 3 but I just get "E2E4146A36E9C455CF95A4F259F162C353CD419CC3FD0E69AE36D7D1B6CD2C09"

What am I doing wrong?