PIC16LF720_11 Datasheet, PDF (71/244 Pages) Microchip Technology – 20-Pin Flash Microcontrollers with nanoWatt XLP Technology

7.6 External Clock Modes
7.6.1 EC MODE
The External Clock (EC) mode allows an externally
generated logic level as the system clock source. When
operating in this mode, an external clock source is
connected to the CLKOUT input and the CLKIN is
available for general purpose I/O. Figure 7-2 shows the
pin connections for EC mode.
FIGURE 7-2:
EXTERNAL CLOCK (EC)
MODE OPERATION
Clock from
Ext. System
I/O
CLKIN
PIC^® MCU
CLKOUT
PIC16(L)F720/721
TABLE 7-1: SUMMARY OF REGISTERS ASSOCIATED WITH CLOCK SOURCES
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Value on
POR, BOR
Value on
all other
Resets⁽¹⁾
CONFIG1⁽¹⁾
—
CP MCLRE PWRTE WDTEN
—
FOSC1 FOSC0
—
—
OSCCON
—
—
IRCF1 IRCF0 ICSL ICSS
—
—
--10 qq-- --10 qq--
OSCTUNE
—
—
TUN5 TUN4 TUN3 TUN2 TUN1 TUN0 --00 0000 --uu uuuu
Legend: x = unknown, u = unchanged, – = unimplemented locations read as ‘0’. Shaded cells are not used by oscillators.
Note 1: See Configuration Word 1 (Register 8-1) for operation of all bits.
 2011 Microchip Technology Inc.
Preliminary
DS41430B-page 71