2004 Microchip Technology Inc.
Advance Information
DS70119B-page 137
dsPIC30F6010
21.2
Oscillator Configurations
21.2.1
INITIAL CLOCK SOURCE
SELECTION
While coming out of Power-on Reset or Brown-out
Reset, the device selects its clock source based on:
a)
FOS<1:0> configuration bits that select one of
four oscillator groups.
b)
AND FPR<3:0> configuration bits that select
one of 13 oscillator choices within the primary
group.
The selection is as shown in Table 21-2.
TABLE 21-2:
CONFIGURATION BIT VALUES FOR CLOCK SELECTION
21.2.2
OSCILLATOR START-UP TIMER
(OST)
In order to ensure that a crystal oscillator (or ceramic
resonator) has started and stabilized, an oscillator
start-up timer is included. It is a simple 10-bit counter
that counts 1024 T
OSC
cycles before releasing the
oscillator clock to the rest of the system. The time-out
period is designated as T
OST
. The T
OST
time is involved
every time the oscillator has to restart (i.e., on POR,
BOR and wake-up from Sleep). The oscillator start-up
timer is applied to the LP Oscillator, XT, XTL, and HS
modes (upon wake-up from Sleep, POR and BOR) for
the primary oscillator.
21.2.3
LP OSCILLATOR CONTROL
Enabling the LP oscillator is controlled with two
elements:
1.
The current oscillator group bits COSC<1:0>.
2.
The LPOSCEN bit (OSCON register).
The LP oscillator is ON (even during Sleep mode) if
LPOSCEN =
1
. The LP oscillator is the device clock if:
• COSC<1:0> =
00
(LP selected as main oscillator)
and
• LPOSCEN =
1
Keeping the LP oscillator ON at all times allows for a
fast switch to the 32 kHz system clock for lower power
operation. Returning to the faster main oscillator will
still require a start-up time.
Oscillator Mode
Oscillator
Source
FOS1
FOS0
FPR3
FPR2
FPR1
FPR0
OSC2
Function
EC
Primary
1
1
1
0
1
1
CLKO
ECIO
Primary
1
1
1
1
0
0
I/O
EC w/ PLL 4x
Primary
1
1
1
1
0
1
I/O
EC w/ PLL 8x
Primary
1
1
1
1
1
0
I/O
EC w/ PLL 16x
Primary
1
1
1
1
1
1
I/O
ERC
Primary
1
1
1
0
0
1
CLKO
ERCIO
Primary
1
1
1
0
0
0
I/O
XT
Primary
1
1
0
1
0
0
OSC2
XT w/ PLL 4x
Primary
1
1
0
1
0
1
OSC2
XT w/ PLL 8x
Primary
1
1
0
1
1
0
OSC2
XT w/ PLL 16x
Primary
1
1
0
1
1
1
OSC2
XTL
Primary
1
1
0
0
0
X
OSC2
HS
Primary
1
1
0
0
1
X
OSC2
LP
Secondary
0
0
—
—
—
—
(Notes 1, 2)
FRC
Internal FRC
0
1
—
—
—
—
(Notes 1, 2)
LPRC
Internal LPRC
1
0
—
—
—
—
(Notes 1, 2)
Note 1:
OSC2 pin function is determined by the Primary Oscillator mode selection (FPR<3:0>).
2:
Note that OSC1 pin cannot be used as an I/O pin, even if the secondary oscillator or an internal clock
source is selected at all times.
Summary of Contents for dsPIC30F6010
Page 12: ...dsPIC30F6010 DS70119B page 10 Advance Information 2004 Microchip Technology Inc NOTES...
Page 32: ...dsPIC30F6010 DS70119B page 30 Advance Information 2004 Microchip Technology Inc NOTES...
Page 38: ...dsPIC30F6010 DS70119B page 36 Advance Information 2004 Microchip Technology Inc NOTES...
Page 50: ...dsPIC30F6010 DS70119B page 48 Advance Information 2004 Microchip Technology Inc NOTES...
Page 68: ...dsPIC30F6010 DS70119B page 66 Advance Information 2004 Microchip Technology Inc NOTES...
Page 72: ...dsPIC30F6010 DS70119B page 70 Advance Information 2004 Microchip Technology Inc NOTES...
Page 76: ...dsPIC30F6010 DS70119B page 74 Advance Information 2004 Microchip Technology Inc NOTES...
Page 86: ...dsPIC30F6010 DS70119B page 84 Advance Information 2004 Microchip Technology Inc NOTES...
Page 108: ...dsPIC30F6010 DS70119B page 106 Advance Information 2004 Microchip Technology Inc NOTES...
Page 116: ...dsPIC30F6010 DS70119B page 114 Advance Information 2004 Microchip Technology Inc NOTES...
Page 128: ...dsPIC30F6010 DS70119B page 126 Advance Information 2004 Microchip Technology Inc NOTES...
Page 150: ...dsPIC30F6010 DS70119B page 148 Advance Information 2004 Microchip Technology Inc NOTES...
Page 164: ...dsPIC30F6010 DS70119B page 162 Advance Information 2004 Microchip Technology Inc NOTES...
Page 208: ...dsPIC30F6010 DS70119B page 206 Advance Information 2004 Microchip Technology Inc NOTES...
Page 220: ...dsPIC30F6010 DS70119B page 220 Advance Information 2004 Microchip Technology Inc NOTES...
Page 221: ...2004 Microchip Technology Inc Advance Information DS70119B page 221 dsPIC30F6010 NOTES...