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Master/slave
configuration
jumpers
Pin 1
Pin 20 removed
for keying
Circuit board
B D
A C
Drive is master; slave may be detected using DASP– signal
Drive is master; Seagate slave drive present
Drive is slave; Seagate master drive present
Use CSEL pin grounding to differentiate master from slave
Figure 1. ATA interface connector and master/slave
configuration jumpers
Marathon 420sl Installation Guide, August 1995
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