Sun Microsystems 1.0, Service Manual

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Figure 5–16 Serial Port Jumper Settings
Clock Speed Jumpers
You must set the system clock speed jumpers on the Main Logic Board to ensure
correct operation of the MBus module. This section describes the jumper settings for
two different types of Main Logic Boards.
Use the following tables to determine the correct jumper settings for your system.
Both tables give the proper jumper settings. See Table 5–1 if you know your system
model number; or see Table 5–2 to find the jumper settings based on your MBus
module numbers.
TABLE 5–1
System Clock Speed Jumper Settings Based on SPARCstation 10 Model
Number
SPARCstation 10 Model Number Jumper Setting
System Clock
Speed MBus Clock
Speed
Model 20 B 66 MHz 33 MHz
Model 30 B 72MHz 36 MHz
Model 40 B 80 MHz 40 MHz
Model 402 MP (2 x SM40) A 80 MHz 40 MHz
Model 41 A 80 MHz 40 MHz
Model 41 MP (2 x SM41) A 80 MHz 40 MHz
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SPARCstation 10 Service Manual
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Revision A, July 1993