PIC16F648A-I/P Microchip Technology, PIC16F648A-I/P Datasheet - Page 30
![IC MCU FLASH 4KX14 EEPROM 18DIP](/photos/6/76/67657/18-dip_300mil__sml.jpg)
PIC16F648A-I/P
Manufacturer Part Number
PIC16F648A-I/P
Description
IC MCU FLASH 4KX14 EEPROM 18DIP
Manufacturer
Microchip Technology
Series
PIC® 16Fr
Datasheets
1.PIC16F616T-ISL.pdf
(8 pages)
2.PIC16F627A-IP.pdf
(180 pages)
3.PIC16F627A-IP.pdf
(8 pages)
4.PIC16F627A-IP.pdf
(22 pages)
5.PIC16F627A-ISO.pdf
(168 pages)
Specifications of PIC16F648A-I/P
Program Memory Type
FLASH
Program Memory Size
7KB (4K x 14)
Package / Case
18-DIP (0.300", 7.62mm)
Core Processor
PIC
Core Size
8-Bit
Speed
20MHz
Connectivity
UART/USART
Peripherals
Brown-out Detect/Reset, POR, PWM, WDT
Number Of I /o
16
Eeprom Size
256 x 8
Ram Size
256 x 8
Voltage - Supply (vcc/vdd)
3 V ~ 5.5 V
Oscillator Type
Internal
Operating Temperature
-40°C ~ 85°C
Processor Series
PIC16F
Core
PIC
Data Bus Width
8 bit
Data Ram Size
256 B
Interface Type
SCI/USART
Maximum Clock Frequency
20 MHz
Number Of Programmable I/os
16
Number Of Timers
3
Operating Supply Voltage
2 V to 5.5 V
Maximum Operating Temperature
+ 85 C
Mounting Style
Through Hole
3rd Party Development Tools
52715-96, 52716-328, 52717-734
Development Tools By Supplier
PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DM163014, DM164120-4
Minimum Operating Temperature
- 40 C
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
For Use With
I3DBF648 - BOARD DAUGHTER ICEPIC3AC162053 - HEADER INTERFACE ICD,ICD2 18DIPACICE0202 - ADAPTER MPLABICE 18P 300 MILAC164010 - MODULE SKT PROMATEII DIP/SOIC
Data Converters
-
Lead Free Status / Rohs Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
PIC16F648A-I/P
Manufacturer:
MICROCHIP
Quantity:
2 100
Part Number:
PIC16F648A-I/P
Manufacturer:
MICROCH
Quantity:
20 000
PIC16F627A/628A/648A
4.3
The Program Counter (PC) is 13-bits wide. The low
byte comes from the PCL register, which is a readable
and writable register. The high byte (PC<12:8>) is not
directly readable or writable and comes from PCLATH.
On any Reset, the PC is cleared. Figure 4-4 shows the
two situations for loading the PC. The upper example
in Figure 4-4 shows how the PC is loaded on a write to
PCL (PCLATH<4:0> → PCH). The lower example in
Figure 4-4 shows how the PC is loaded during a CALL
or GOTO instruction (PCLATH<4:3> → PCH).
FIGURE 4-4:
4.3.1
A computed GOTO is accomplished by adding an offset
to the program counter (ADDWF PCL). When doing a
table read using a computed GOTO method, care
should be exercised if the table location crosses a PCL
memory boundary (each 256-byte block). Refer to the
Application Note AN556 “Implementing a Table Read”
(DS00556).
4.3.2
The PIC16F627A/628A/648A family has an 8-level
deep x 13-bit wide hardware stack (Figure 4-1). The
stack space is not part of either program or data space
and the Stack Pointer is not readable or writable. The
PC is PUSHed onto the stack when a CALL instruction
is executed or an interrupt causes a branch. The stack
is POPed in the event of a RETURN,
RETFIE instruction execution. PCLATH is not affected
by a PUSH or POP operation.
DS40044G-page 30
PC
PC
12
12 11 10
2
PCL and PCLATH
PCH
5
PCLATH<4:3>
PCH
COMPUTED GOTO
STACK
PCLATH
PCLATH<4:0>
8
PCLATH
8
7
7
LOADING OF PC IN
DIFFERENT SITUATIONS
PCL
PCL
11
8
0
0
Instruction with
PCL as
Destination
ALU result
GOTO, CALL
Opcode <10:0>
RETLW or a
The stack operates as a circular buffer. This means that
after the stack has been PUSHed eight times, the ninth
PUSH overwrites the value that was stored from the
first PUSH. The tenth PUSH overwrites the second
PUSH (and so on).
4.4
The INDF register is not a physical register. Addressing
the INDF register will cause indirect addressing.
Indirect addressing is possible by using the INDF
register. Any instruction using the INDF register
actually accesses data pointed to by the File Select
Register (FSR). Reading INDF itself indirectly will
produce 00h. Writing to the INDF register indirectly
results in a no-operation (although Status bits may be
affected). An effective 9-bit address is obtained by
concatenating the 8-bit FSR register and the IRP bit
(STATUS<7>), as shown in Figure 4-5.
A simple program to clear RAM location 20h-2Fh using
indirect addressing is shown in Example 4-1.
EXAMPLE 4-1:
NEXT
Note 1: There are no Status bits to indicate stack
2: There are no instructions/mnemonics
Indirect Addressing, INDF and
FSR Registers
MOVLW
MOVWF
CLRF
INCF
BTFSS
GOTO
overflow or stack underflow conditions.
called PUSH or POP. These are actions
that occur from the execution of the
CALL, RETURN, RETLW and RETFIE
instructions, or the vectoring to an
interrupt address.
0x20
FSR
INDF
FSR
FSR,4
NEXT
INDIRECT ADDRESSING
© 2009 Microchip Technology Inc.
;initialize pointer
;to RAM
;clear INDF register
;inc pointer
;all done?
;no clear next
;yes continue