On May 18, 2019, at 15:10, Rod Smallwood via cctalk <cctalk at classiccmp.org> wrote: Hi Guys Well the RD53 in my 11/93 finally clapped out. The CPU is a late model KDJ11-E with everything on the one board. So its a switch from MFM to SCSI Drives. A CQD220A will drive the hard disk and the RQDX3 will stay to look after the RX50 I've put the Hard Drive on the primary CSR address (17772150) and I will shift the RQDX3 to an alternate CSR Comments as to if this is the right way round and what CSR's to use for the two controllers invited. Rod --