Hi Gerd & Steve I've done another pass through Display to remove lots of casts and masking. This required removed the overloading of Displayer.setBytes(byte/char/short/int) by having setBytes1/2/4() to match the existing setBytes3() DisplayItem.getValue() now returns the same value as fed in with setBytesX(), which also returns this value. I think Displayer.byteValue(), sByteValue, charValue should be changed to return this same int value, this will allow more casts/masks to be removed. In this pass I've tried to keep the exact same final output as the version before any of the IO changes. There are a few places that I've marked with %%% where I think the code is wrong, treating something as signed when it isn't. I don't have any DEM data for testing test.display.DemDisplay but I've done all the other sections. NodConvert gives Exception in thread "main" java.lang.AssertionError at test.display.NodConvert.pointerPart(NodConvert.java:274) if (first) { assert !newdir; but it did this for me with the pre-io-change version Regards Ticker