IBM RT User's Setup Manual page 206

11. Look at the d ia g ra m of the cable bundle th a t applies to your
system.
To Fixed-Disk Drive
C-AB and C-CD or C-CDE are connected to the 34-pin connectors
on the drive ad ap ter, and C-Cl is connected to the 20-pin
connector.
Section 2. Removing an d Installing Drives in IBM 6150
AJZIF065
2-31