As a precursor to H1's upgrade to RCG3.4.2, I have selectively upgraded h1pemmx.

The procedure was:

Clone x1boot1 disk

Install in h1boot-backup and rename this as h1boot1

Make necessary X1 to H1 modifications, remove DTS changes

Install RCG3.4.2 using Rolf's and Keith's Release Notes (DCC-T1700552)

Take h1pemmx out of h1boot and add it to h1boot1

I now have h1pemmx models (h1ioppemmx, h1pemmx) running under 3.4.2. DAQ data looks good. Testpoints look good. Excitations look good.

There is a problem getting everything running on startup. I'll transition a corner station SUS-AUX model to work on this so I don't have to commute 2km.