I've been using the Nibe integration with my S1256 and it's working great. Now I wanted to make use of the SG READY function which recently became writable through modbus instead of just aux inputs. As far as I can tell, this involves enabling the "SG ready via API" switch in holding register 3032 and then setting the actual mode using register 6008.
Both these entities are available but disabled in my integration. I could enable 3032 and also write to it, and its status is confirmed on the display on the unit. However, when I attempt to enable register 6008, it immediately flips back to disabled.
Both of the registers exist in the export of the modbus registers I get from the unit.