MA240029 Microchip Technology, MA240029 Datasheet - Page 150

• Manufacturer Part Number: MA240029
• Description: Daughter Cards & OEM Boards PIC24FJ128GA310 Gen Purpose PIM
• Manufacturer: Microchip Technology

Specifications of MA240029

• Rohs: yes
• Product: Daughter Cards
• Core: PIC
• Description/function: Plug-in module
• Interface Type: I2C, SPI
• Tool Is For Evaluation Of: PIC24FJ128GA310
• For Use With: Explorer 16 Development Board

PIC24FJ128GA310 FAMILY
REGISTER 9-3:
9.4
With few limitations, applications are free to switch
between any of the four clock sources (POSC, SOSC,
FRC and LPRC) under software control and at any
time. To limit the possible side effects that could result
from this flexibility, PIC24F devices have a safeguard
lock built into the switching process.
DS39996F-page 150
bit 15
bit 7
Legend:
R = Readable bit
-n = Value at POR
bit 15-6
bit 5-0
Note 1:
Note:
U-0
U-0
—
—
Clock Switching Operation
Increments or decrements of TUN<5:0> may not change the FRC frequency in equal steps over the FRC
tuning range and may not be monotonic.
The Primary Oscillator mode has three
different submodes (XT, HS and EC)
which are determined by the POSCMDx
Configuration bits. While an application
can switch to and from Primary Oscillator
mode in software, it cannot switch
between the different primary submodes
without reprogramming the device.
Unimplemented: Read as ‘0’
TUN<5:0>: FRC Oscillator Tuning bits
011111 = Maximum frequency deviation
011110 =



000001 =
000000 = Center frequency, oscillator is running at factory calibrated frequency
111111 =



100001 =
100000 = Minimum frequency deviation
U-0
U-0
—
—
OSCTUN: FRC OSCILLATOR TUNE REGISTER
W = Writable bit
‘1’ = Bit is set
TUN5
R/W-0
U-0
—
(1)
TUN4
R/W-0
U-0
—
(1)
(1)
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
TUN3
R/W-0
Monitor function are disabled. This is the default setting.
9.4.1
To enable clock switching, the FCKSM Configuration bits
in CW2 must be programmed to ‘00’. (Refer to
Section 29.1 “Configuration Bits”
If the FCKSM Configuration bits are unprogrammed
(‘1x’), the clock switching function and Fail-Safe Clock
The NOSCx control bits (OSCCON<10:8>) do not
control the clock selection when clock switching is dis-
abled. However, the COSCx bits (OSCCON<14:12>)
will reflect the clock source selected by the FNOSCx
Configuration bits.
The OSWEN control bit (OSCCON<0>) has no effect
when clock switching is disabled. It is held at ‘0’ at all
times.
U-0
—
(1)
ENABLING CLOCK SWITCHING
TUN2
R/W-0
U-0
—
 2010-2011 Microchip Technology Inc.
(1)
x = Bit is unknown
TUN1
R/W-0
U-0
—
(1)
for further details.)
TUN0
R/W-0
U-0
—
(1)
bit 8
bit 0