Sun Microsystems Blade 1500 - Other Buses; C.4.6 Other Buses

C-20 Sun Blade 1500 Service, Diagnostics, and Troubleshooting Manual • December 2004
FIGURE C-6 BCM5793 Block Diagram
C.4.6 Other Buses
Other buses are used in the Sun Blade 1500 workstation for interfacing various
components:
■ I
2
C — for fan control, motherboard FRU ID, PCI clock generator, and DIMM flash
PROMs
■ Ichip2 — interrupt concentrator
■ XBus — for real-time clock, firmware, 32K SRAM, and I
2
C master
■ SMBus — for smart card reader
■ ATA 100 — for hard drives and optical media drive
Note – A second I
2
C bus interfaces the NVRAM with the JIO I/O bridge.
Memory
controller
Buffer
memory
PCI I/F
PLL LED control SMBus
EEPROM
control
PLL
32-KB
memory
Dual
processor
10/100/1000
MAC
10/100/1000
PHY
LED signals SMB interface EEPROM interface
PCI
bus
PCI
clk
RX
TX