PLX Technology PEX 8505, Справочник по аппаратуре

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PEX 8505RDK Hardware Reference Manual v1.1
© 2007, PLX Technology, Inc. All rights reserved.
11
3. On-Board Connectors, Switches, and Jumpers
3.1 DIP Switches
The PEX 8505RDK contains four user controllable DIP switches (SW1, SW2, SW3 and SW4) for
selecting various functionality. Each DIP switch position can be either ON (0b) or OFF (1b). The gray
squares in Figures 3-1 through 3-4 indicate which way the switch position is connected.
3.1.1 Upstream Port Selection (SW1)
Figure 3-1. Switch SW1 Default Settings
Table 3-1. Switch SW1 Description
SW1 Functional Description Switch Position Settings
STRAP_UPSTRM_PORTSEL [2:0]
Selects the PEX 8505 Upstream Port.
Default setting is 000b.
1: STRAP_UPSTRM_PORTSEL[0]
2: STRAP_UPSTRM_PORTSEL[1]
3: STRAP_UPSTRM_PORTSEL[2]
Bus Encodings [2:0] Upstream Port
000b 0
001b 1
010b 2
011b 3
100b 4
101b 5
110b 6
111b 7
3.1.2 PEX 8505 I2C Address Selection (SW2)
Switch SW2 is used to select the lower three address bits of the PEX 8505’s I2C slave address.
Figure 3-2. Switch SW2 Default Settings
SW1
ON
UP_PORT0
HIGH
LOW
1
1
2
ON
2
3
3
UP_PORT1
UP_PORT2
SW2
ON
I2C_ADDR0
HIGH
LOW
1
1
2
ON
2
3
3
I2C_ADDR1
I2C_ADDR2