To the excellent encapsulations of register and tomlee59 I should add only that termination power may become insufficient in a full SCSI daisy-chain. If any of the devices in the middle of the chain is capable of it, setting supply of 'termination power to the bus' on those devices may augment the available power. (Many Seagate drives, for example, allow this by jumpering the last pin pair, TP, on the underside header block J2. Do not, however, also enable the 'termination enable' pair TE at the other end of the block on such drives in the middle of the chain.)

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