LM3S328 Luminary Micro, Inc., LM3S328 Datasheet - Page 78

• Manufacturer Part Number: LM3S328
• Description: Microcontroller
• Manufacturer: Luminary Micro, Inc.

System Control
78
Bit/Field
9:6
5:4
10
11
3
2
1
0
MOSCVER
MOSCDIS
IOSCVER
OSCSRC
IOSCDIS
BYPASS
PLLVER
Name
XTAL
Type
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset
Oscillator-Related Bits
0xB
0x0
1
0
0
0
0
0
Preliminary
Description
PLL Bypass
Chooses whether the system clock is derived from the PLL
output or the OSC source. If set, the clock that drives the
system is the OSC source. Otherwise, the clock that drives
the system is the PLL output clock divided by the system
divider.
Note:
PLL Verification
This bit controls the PLL verification timer function. If set,
the verification timer is enabled and an interrupt is
generated if the PLL becomes inoperative. Otherwise, the
verification timer is not enabled.
This field specifies the crystal value attached to the main
oscillator. The encoding for this field is provided in Table 6-4
on page 79.
Picks among the four input sources for the OSC. The
values are:
function. If set, the verification timer is enabled and an
interrupt is generated if the timer becomes inoperative.
Otherwise, the verification timer is not enabled.
function. If set, the verification timer is enabled and an
interrupt is generated if the timer becomes inoperative.
Otherwise, the verification timer is not enabled.
Internal Oscillator Disable
0: Internal oscillator is enabled.
1: Internal oscillator is disabled.
Main Oscillator Disable
0: Main oscillator is enabled.
1: Main oscillator is disabled.
This bit controls the internal oscillator verification timer
This bit controls the main oscillator verification timer
Value
00
01
10
11
The ADC module cannot be used when the PLL is
in Bypass mode (BYPASS set to 1).
Input Source
Main oscillator (default)
Internal oscillator
Internal oscillator / 4 (this is necessary if used
as input to PLL)
reserved
October 8, 2006