FUJITSU Disk Drives MHJ2181AT - Manual (Page 189)

Interface
5-116 C141-E088-01EN
5.6.4 Power-on and reset
Figure 5.22 shows power-on and reset (hardware and software reset) timing.
(1) Only master device is present
(2) Master and slave devices are present (2-drives configulation)
Figure 5.22 Power on Reset Timing
31
Power-on Reset
RESET–
PDIAG- negation