Sun Microsystems 1.0, Service Manual

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TABLE 5–1
System Clock Speed Jumper Settings Based on SPARCstation 10 Model
Number
(continued)
SPARCstation 10 Model Number Jumper Setting
System Clock
Speed MBus Clock
Speed
Model 51 A 80 MHz 40 MHz
Model 512 MP (2x SM51) A 80 MHz 40 MHz
TABLE 5–2
System Clock Speed Jumper Settings Based on MBus Module
MBus Module
1
Part Number Jumper Setting
System Clock
Speed MBus Clock
Speed
SM20 501-2218 B 66 MHz 33 MHz
SM30 501-2215
501-2239
B 72 MHz 36 MHz
SM40 501-2219
501-2358
B 80 MHz 40 MHz
SM41 501-2258
501-2270
501-2359
A 80 MHz 40 MHz
SM51 501-2352
501-2360
A 80 MHz 40 MHz
1. SM refers to SPARC Module.
Three Clock Speed Jumpers
The first type of board has three jumpers (J1401, J1403, J1404). All three jumpers must
be set for either mode A operation (step one), or mode B operation (step two), based
on the system model number or MBus modules installed.
1. Set the mode A clock speed jumpers.
Use a pair of needle nose pliers to move the jumpers to the correct positions. See
Figure 5–17.
Main Logic Board
53