c)In a system which does not use the terminating resistor power supply signal (TERMPWR) on the SCSI bus, the requirements for +5 VDC given in Figure 4.10 must be satisfied between the HDD and the SCSI device with the terminating resistor circuit.
SCSI devices with the terminating resistor
Figure 4.10 Power on/off sequence (2)
d)Between the HDD and other SCSI devices on the SCSI bus, the +5 VDC power on/off sequence is as follows:
•In a system with its all SCSI devices designed to prevent noise from leaking to the SCSI bus when power is turned on or off, the power sequence does not matter if the requirement in b) or c) is satisfied.
•In a system containing an SCSI device which is not designed to prevent noise from leaking to the SCSI bus, the requirement given in Figure 4.11 must be satisfied between that SCSI device and the HDD.
SCSI devices without noise leaking designed
Figure 4.11 Power on/off sequence (3)
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