
IDT SMBus Interfaces
PES32NT24xG2 User Manual
12 - 13
January 30, 2013
Notes
The following I/O expander configuration sequence is issued by the switch to I/O expanders 0 through
11, 14, 15, and 16 (i.e., the ones that contain general port hot-plug signals and electromechanical interlock
signals). The I/O expander registers in the sequence are located in the I/O expander device.
1. Write the default value of the outputs bits on the lower eight I/O expander pins (i.e., I/O-0.0 through
I/O-0.7) to I/O expander register 2.
2. Write the default value of the outputs bits on the upper eight I/O expander pins (i.e., I/O-1.0 through
I/O-1.7) to I/O expander register 3.
3. Write value 0x0 to I/O expander register 4 (no inversion in IO-0)
4. Write value 0x0 to I/O expander register 5 (no inversion in IO-1)
5. Write the configuration value to select inputs/outputs in the lower eight I/O expander bits (i.e., I/O-
0.0 through I/O-0.7) to I/O expander register 6.
6. Write the configuration value to select inputs/outputs in the upper eight I/O expander bits (i.e., I/O-
1.0 through I/O-1.7) to I/O expander register 7.
7. Read value of I/O expander register 0 to obtain the current state of the lower eight I/O expander bits
(i.e., I/O-0.0 through I/O-0.7)
8. Read value of I/O expander register 1 to obtain the current state of the upper eight I/O expander bits
(i.e., I/O-1.0 through I/O-1.7)
The following I/O expander configuration sequence is issued by the switch to I/O expanders 12 and 13
(i.e., the ones that contain MRL and partition fundamental reset inputs).
1. Write value 0x0 to I/O expander register 4 (no inversion in IO-0)
2. Write value 0x0 to I/O expander register 5 (no inversion in IO-1)
3. Write the configuration value to select all inputs in the lower eight I/O expander bits (i.e., I/O-0.0
through I/O-0.7) to I/O expander register 6.
4. Write the configuration value to select all inputs in the upper eight I/O expander bits (i.e., I/O-1.0
through I/O-1.7) to I/O expander register 7.
5. Read value of I/O expander register 0 to obtain the current state of the lower eight I/O expander bits
(i.e., I/O-0.0 through I/O-0.7)
6. read value of I/O expander register 1 to obtain the current state of the upper eight I/O expander bits
(i.e., I/O-1.0 through I/O-1.7)
The following I/O expander configuration sequence is issued by the switch to I/O expanders 17, 18, and
19 (i.e., the one that contains link up and link activity status).
1. Write link up status for all ports to the lower eight I/O expander pins (i.e., I/O-0.0 through I/O-0.7) to
I/O expander register 2.
2. Write link activity status for all ports to the upper eight I/O expander pins (i.e., I/O-1.0 through I/O-
1.7) to I/O expander register 3.
3. Write value 0x0 to I/O expander register 4 (no inversion in IO-0)
4. Write value 0x0 to I/O expander register 5 (no inversion in IO-1)
5. Write the configuration value to select all outputs in the lower eight I/O expander bits (i.e., I/O-0.0
through I/O-0.7) to I/O expander register 6.
6. Write the configuration value to select all outputs in the upper eight I/O expander bits (i.e., I/O-1.0
through I/O-1.7) to I/O expander register 7.
Summary of Contents for PCI Express 89HPES32NT24xG2
Page 20: ...IDT Table of Contents PES32NT24xG2 User Manual x January 30 2013 Notes...
Page 24: ...IDT List of Tables PES32NT24xG2 User Manual xiv January 30 2013 Notes...
Page 28: ...IDT List of Figures PES32NT24xG2 User Manual xviii January 30 2013 Notes...
Page 56: ...IDT PES32NT24xG2 Device Overview PES32NT24xG2 User Manual 1 20 January 30 2013 Notes...
Page 100: ...IDT Switch Core PES32NT24xG2 User Manual 4 22 January 30 2013 Notes...
Page 128: ...IDT Failover PES32NT24xG2 User Manual 6 4 January 30 2013 Notes...
Page 148: ...IDT Link Operation PES32NT24xG2 User Manual 7 20 January 30 2013 Notes...
Page 164: ...IDT SerDes PES32NT24xG2 User Manual 8 16 January 30 2013 Notes...
Page 170: ...IDT Power Management PES32NT24xG2 User Manual 9 6 January 30 2013 Notes...
Page 196: ...IDT Transparent Switch Operation PES32NT24xG2 User Manual 10 26 January 30 2013 Notes...
Page 244: ...IDT SMBus Interfaces PES32NT24xG2 User Manual 12 40 January 30 2013 Notes...
Page 247: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 3 January 30 2013 Notes...
Page 248: ...IDT General Purpose I O PES32NT24xG2 User Manual 13 4 January 30 2013 Notes...
Page 330: ...IDT Switch Events PES32NT24xG2 User Manual 16 6 January 30 2013 Notes...
Page 342: ...IDT Multicast PES32NT24xG2 User Manual 17 12 January 30 2013 Notes...
Page 344: ...IDT Temperature Sensor PES32NT24xG2 User Manual 18 2 January 30 2013 Notes...
Page 384: ...IDT Register Organization PES32NT24xG2 User Manual 19 40 January 30 2013...
Page 492: ...IDT Proprietary Port Specific Registers PES32NT24xG2 User Manual 21 44 January 30 2013 Notes...
Page 588: ...IDT NT Endpoint Registers PES32NT24xG2 User Manual 22 96 January 30 2013 Notes...
Page 710: ...IDT JTAG Boundary Scan PES32NT24xG2 User Manual 25 12 January 30 2013 Notes...
Page 743: ...IDT Usage Models PES32NT24xG2 User Manual 26 33 January 30 2013 Notes...
Page 744: ...IDT Usage Models PES32NT24xG2 User Manual 26 34 January 30 2013 Notes...