Figure 3-1. gpio switch settings (s1), Table 3-1. gpio pin assignments – Emerson I/O MODULE IPMC7126E User Manual
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IPMC7126E/7616E I/O Module Installation and Use (6806800A45B)
Chapter 3 Programming
16
The General Purpose I/O (GPIO) pin assignments for the SCSI Controller are shown in the
table below. A 1x4 switch (S1) is provided to configure GPIO pins 2 and 3. The factory default
setting shall be for Ultra-Speed and Ultra-Wide SCSI.
SW1-P1 controls GPIO2 (Ultra/FAST SCSI) and SW1-P2 controls GPIO3 (Wide/Narrow SCSI
bus. SW1-P3 and SW1-P4 are No Connect. Select the SCSI characteristics of your
configuration according to the following table:
Table 3-1. GPIO Pin Assignments
GPIO Pin
Direction
Level
Usage
GPIO1_MASTER_l
output
1
SCSI LED; SCSI is not MASTER.
0
SCSI is MASTER.
GPIO2
input
1
SCSI speed; selectable by switch S1.
S1:1 OFF selects Ultra
0
S1:1 ON selects FAST (default).
GPIO3
input
1
SCSI bus width; selectable by switch S1.
S1:2 in OFF selects Wide-SCSI.
0
S1:2 in ON selects Narrow-SCSI.
0, 4, 5, 6, 7, 8
-
-
Not used.
Table 3-2. SCSI Speed/Width Settings Using GPIO2:[1,2]
SCSI Type
Width
Speed
FAST SCSI
Narrow (8 bit)
10MB/second
FAST SCSI
Wide (16 bit)
20MB/second
Ultra SCSI
Narrow (8 bit)
20MB/second
Ultra SCSI
Narrow (16 bit)
40MB/second
Figure 3-1. GPIO Switch Settings (S1)
Width of Bus
Ultra (P1 OFF)
Fast (P1 ON)
Wide (16-bit) SCSI bus (P2 OFF)
40MB/second
20MB/second
Narrow (8-bit) SCSI bus (P2 ON)
20MB/second
10MB/second
ON
ON
1
1
8
8
S1-P3=1
S1-P4=1
S1-P2=1
S1-P1=1
S1-P3=0
S1-P4=0
S1-P2=0
S1-P1=0