PIC16LCE625-04I/SS Microchip Technology, PIC16LCE625-04I/SS Datasheet - Page 23

• Manufacturer Part Number: PIC16LCE625-04I/SS
• Description: IC MCU CMOS 2K OTP W/EEPRM20SSOP
• Manufacturer: Microchip Technology
• Series: PIC® 16Cr

Specifications of PIC16LCE625-04I/SS

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 4MHz
• Peripherals: Brown-out Detect/Reset, POR, WDT
• Number Of I /o: 13
• Program Memory Size: 3.5KB (2K x 14)
• Program Memory Type: OTP
• Eeprom Size: 128 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 2.5 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Data Converters: -
• Connectivity: -
• Other names: PIC16LCE62504I/SS

5.0
The PIC16CE62X parts have two ports, PORTA and
PORTB. Some pins for these I/O ports are multiplexed
with an alternate function for the peripheral features on
the device. In general, when a peripheral is enabled,
that pin may not be used as a general purpose I/O pin.
5.1
PORTA is a 5-bit wide latch. RA4 is a Schmitt Trigger input
and an open drain output. Port RA4 is multiplexed with the
T0CKI clock input. All other RA port pins have Schmitt
Trigger input levels and full CMOS output drivers. All pins
have data direction bits (TRIS registers), which can con-
figure these pins as input or output.
A ’1’ in the TRISA register puts the corresponding output
driver in a hi- impedance mode. A ’0’ in the TRISA register
puts the contents of the output latch on the selected pin(s).
Reading the PORTA register reads the status of the pins,
whereas writing to it will write to the port latch. All write
operations are read-modify-write operations. So a write
to a port implies that the port pins are first read, then this
value is modified and written to the port data latch.
The PORTA pins are multiplexed with comparator and
voltage reference functions. The operation of these
pins are selected by control bits in the CMCON
(Comparator Control Register) register and the
VRCON (Voltage Reference Control Register) register.
When selected as a comparator input, these pins will
read as ’0’s.
FIGURE 5-1:
WR
TRISA
Data
Bus
WR
PortA
1999 Microchip Technology Inc.
RD PORTA
I/O PORTS
PORTA and TRISA Registers
To Comparator
D
D
TRIS Latch
Data Latch
CK
CK
RD TRISA
BLOCK DIAGRAM OF
RA<1:0> PINS
Q
Q
Q
Q
Input Mode
Q
Schmitt Trigger
Analog
Input Buffer
EN
V
V
P
N
D
DD
SS
V
DD
I/O Pin
TRISA controls the direction of the RA pins, even when
they are being used as comparator inputs. The user
must make sure to keep the pins configured as inputs
when using them as comparator inputs.
The RA2 pin will also function as the output for the
voltage reference. When in this mode, the V
very high impedance output. The user must configure
TRISA<2> bit as an input and use high impedance
loads.
In one of the comparator modes defined by the
CMCON register, pins RA3 and RA4 become outputs
of the comparators. The TRISA<4:3> bits must be
cleared to enable outputs to use this function.
EXAMPLE 5-1:
CLRF
MOVLW 0X07
MOVWF CMCON
BSF
MOVLW 0x1F
MOVWF TRISA
FIGURE 5-2:
WR
TRISA
Data
Bus
WR
PortA
Note:
RD PORTA
PORTA
STATUS, RP0 ;Select Bank1
To Comparator
TRIS Latch
D
D
Data Latch
On reset, the TRISA register is set to all
inputs. The digital inputs are disabled and
the comparator inputs are forced to ground
to reduce excess current consumption.
CK
CK
V
RD TRISA
V
ROE
REF
BLOCK DIAGRAM OF RA2 PIN
Q
Q
Q
Q
INITIALIZING PORTA
PIC16CE62X
;Initialize PORTA by setting
;output data latches
;Turn comparators off and
;enable pins for I/O
;functions
;Value used to initialize
;data direction
;Set RA<4:0> as inputs
;TRISA<7:5> are always
;read as ’0’.
Input Mode
Q
Schmitt Trigger
Analog
Input Buffer
EN
V
V
P
N
D
DS40182C-page 23
DD
SS
V
DD
REF
RA2 Pin
pin is a