Will Trimble machine control accept an XML file of a DTM for earthwork, or does it need to be converted to something else? I'm using Carlson civil survey software.
No it will not accept an XML or a DTM. You can export a design that contains a DTM but only through a Trimble data collector using SCS900.
You can download a free edition of BC HCE and convert it though here's a link
http://www.trimble.com/globalTRL.asp?nav=Collection-51337
You could also send me the files and i could convert them for you.
A youtube how to on converting files using BC HCE
You should be able to export the tin as a ttm file.
TIN2TTM
I have had problems on some jobs, so the alternative is to export the surface as a XML file and import that into BC-HCE and export to the surface as a SVD file for GCS or TTM for SCS.
In Carlson Civil 2013 under SURFACE/IMPORT EXPORT SURFACE DATA/Export Trimble TTM file
Our company is making the transition from Topcon HL+ setups to Trimble units. From my experience using Carlson Civil/Survey 2012 to export to TTM files to the controllers is that the TTM file still needs to be exported through TBC especially for the GCS units (dozer, etc.). The GCS unit that we have will not generate contours based on the TTM so I must also include polyline contours in my linework files for the operator to be able to see them.
Perhaps you need to contact your Carlson VAR and ask him about the Carlson Machine Control software they have. Might make for a smoother conversion and output solution.