Drive Addressing and Interface Termination
NOT
USED
J12 J2 J1 J3
____ ________ ___________________ _ _________
| | | |1| | |1| | | POWER |
| |_| |____| |_| |_________|
| |
| RN11 :::::::: |
| DDDWWWWW W28: |
| AAA54321 |
| 321 |
| |
| |
| |
| (Component Side) |
| _|
| |
| |_
| |
| |
1538-series drives require the use of an ESDI Controller capable
of a data transfer rate of at least 23.33 Mbits/sec.
The Interface Terminator factory installed at RN11 will provide
proper termination for the interface lines. When daisy-chaining
multiple drives, leave the terminator installed only in the last
physical drive on the daisy chain cable; remove the terminator from
each of the other drives. In most PC/AT installations, the C: drive
is actually at the end of the cable and should retain the
terminator.
The drive address jumpers are identified as DA1,DA2 and DA3.
Address selection is binary, as shown in the table below. The ESDI
controllers's documentation will specify the drive address to use.
| Drive |
Select Jumpers |
| Address |
DA3 |
DA2 |
DA1 |
| 1 |
out |
out |
in |
| 2 |
out |
in |
out |
| 3 |
out |
in |
in |
| 4 |
in |
out |
out |
| 5 |
in |
out |
in |
| 6 |
in |
in |
out |
| 7 |
in |
in |
in |
"Drive address 0" (no jumper at DA1,DA2, or DA3) is a "deselect"
(i.e., no drive selected).
Drives are factory configured as Drive Address 1.
For many multiple drive installations, each drive must have a unique
address. An exception is that for every drive in a PC/AT
installation, verify that only Drive Address is at DA2; move the
jumper if necessary (the special twisted interface cable that is
generally used takes care of assigning a unique address to each
drive). PC/AT controller can typically support a maximum of two
drives.
Spindle Control Option
Jumper W5 selects the spindle control option.
When W5 is installed, the drive must wait for a start spindle
command to start the spindle motor.
When W5 is not installed (the factory default configuration), the
drive automatically starts the spindle motor at power on.
Sectoring Options
* W1 is not used and must not be jumpered.
Frame ground Options
W28 is to select the frame ground option.
When a jumper is installed at W28, frame ground is connected to
logic ground.
When a jumper is NOT installed at W28 (the factory default
configuration), frame ground is not connected to logic ground.
Sectoring Options
* The number of bytes per sector may be specified using the Set
Bytes Per Sector command or by selecting a default sector
configuration with jumpers W2, W3, and W4 as follows:
| Jumpers |
Sectors |
Bytes / Sector |
| W4 |
W3 |
W2 |
Per Track |
Formatted |
Unformatted |
| out |
out |
out |
68 |
520 |
612 |
| * out |
out |
in |
71 |
512 |
582 |
| out |
in |
out |
38 |
1024 |
1096 |
| out |
in |
in |
18 |
2244 |
2314 |
| in |
out |
out |
10 |
4096 |
4166 |
| in |
out |
in |
58 |
768 |
839 |
| in |
in |
out |
121 |
272 |
342 |
| in |
in |
in |
1 |
41594 |
41664 |
* This is the default (factory installed) configuration and is
recommended for PC/AT applications |
