Switch Sw501; Switch Sw501, Position 1, Pll Enable/Disable; Figure 2-13, Sw501 Layout - Spectrum Digital eZdsp R2812 USB Technical Reference

2.5 Switch SW501

The eZdsp R2812 has a 4 position switch that allows the user to configure the board for
their application. The function of each position is shown in the table below.

2.5.1 Switch SW501, Position 1, PLL Enable/Disable

Position 1 on switch SW501 is used to enable/disable the use of the Phase Lock Loop
(PLL) logic on the DSP. The selection of the open position enables the use of the PLL.
If the closed position is used the PLL is disabled. This signal is latched at reset and
may be used as XF after reset. The positions are shown in the table below.
Table 13: SW501 Switch Positions
Position
1 PLL Enable/Disable
2
3, 4
1
2
3
4
Open/High | Closed/Low
Default from factory

Figure 2-13, SW501 Layout

Table 14: SW501, Position 1
Position
Open-1 *
Closed-0
* as shipped from the factory
Function
MP/MC Select
Boot Mode Select
XF_XPLLDISn
XMP_MCn
SPICLKA
MDXA
Function
PLL Enabled
PLL disabled
Spectrum Digital, Inc
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