PIC18F86J50T-I/PT Microchip Technology, PIC18F86J50T-I/PT Datasheet - Page 73

• Manufacturer Part Number: PIC18F86J50T-I/PT
• Description: IC,MICROCONTROLLER,8-BIT,PIC CPU,CMOS,TQFP,64PIN,PLASTIC
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F86J50T-I/PT

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 48MHz
• Connectivity: EBI/EMI, I²C, SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 65
• Program Memory Size: 64KB (32K x 16)
• Program Memory Type: FLASH
• Ram Size: 3.8K x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 3.6 V
• Data Converters: A/D 12x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-TFQFP
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 3904 B
• Interface Type: I2C, MSSP, SPI, EUSART
• Maximum Clock Frequency: 48 MHz
• Number Of Programmable I/os: 65
• Number Of Timers: 5
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, ICE4000, DV164136, DM183022, DM183032
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 12 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC162087 - HEADER MPLAB ICD2 18F87J50 68/84MA180021 - MODULE PLUG-IN 18F87J50 FS USBAC164328 - MODULE SKT FOR 80TQFP
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: PIC18F86J50T-I/PTTR

5.1.5
The Program Counter (PC) specifies the address of the
instruction to fetch for execution. The PC is 21 bits wide
and is contained in three separate 8-bit registers. The
low byte, known as the PCL register, is both readable
and writable. The high byte, or PCH register, contains
the PC<15:8> bits; it is not directly readable or writable.
Updates to the PCH register are performed through the
PCLATH register. The upper byte is called PCU. This
register contains the PC<20:16> bits; it is also not
directly readable or writable. Updates to the PCU
register are performed through the PCLATU register.
The contents of PCLATH and PCLATU are transferred
to the program counter by any operation that writes
PCL. Similarly, the upper two bytes of the program
counter are transferred to PCLATH and PCLATU by an
operation that reads PCL. This is useful for computed
offsets to the PC (see Section 5.1.8.1 “Computed
GOTO”).
The PC addresses bytes in the program memory. To
prevent the PC from becoming misaligned with word
instructions, the Least Significant bit of PCL is fixed to
a value of ‘0’. The PC increments by 2 to address
sequential instructions in the program memory.
The CALL, RCALL, GOTO and program branch
instructions write to the program counter directly. For
these instructions, the contents of PCLATH and
PCLATU are not transferred to the program counter.
5.1.6
The return address stack allows any combination of up
to 31 program calls and interrupts to occur. The PC is
pushed onto the stack when a CALL or RCALL instruc-
tion is executed, or an interrupt is Acknowledged. The
PC value is pulled off the stack on a RETURN, RETLW
or a RETFIE instruction (and on ADDULNK and
SUBULNK instructions if the extended instruction set is
enabled). PCLATU and PCLATH are not affected by
any of the RETURN or CALL instructions.
FIGURE 5-4:
© 2009 Microchip Technology Inc.
PROGRAM COUNTER
RETURN ADDRESS STACK
Top-of-Stack Registers
TOSU
00h
RETURN ADDRESS STACK AND ASSOCIATED REGISTERS
TOSH
1Ah
TOSL
34h
Top-of-Stack
Return Address Stack <20:0>
001A34h
000D58h
PIC18F87J50 FAMILY
The stack operates as a 31-word by 21-bit RAM and a
5-bit Stack Pointer, STKPTR. The stack space is not
part of either program or data space. The Stack Pointer
is readable and writable and the address on the top of
the stack is readable and writable through the
Top-of-Stack Special Function Registers. Data can also
be pushed to, or popped from the stack, using these
registers.
A CALL type instruction causes a push onto the stack.
The Stack Pointer is first incremented and the location
pointed to by the Stack Pointer is written with the
contents of the PC (already pointing to the instruction
following the CALL). A RETURN type instruction causes
a pop from the stack. The contents of the location
pointed to by the STKPTR are transferred to the PC
and then the Stack Pointer is decremented.
The Stack Pointer is initialized to ‘00000’ after all
Resets. There is no RAM associated with the location
corresponding to a Stack Pointer value of ‘00000’; this
is only a Reset value. Status bits indicate if the stack is
full, has overflowed or has underflowed.
5.1.6.1
Only the top of the return address stack (TOS) is read-
able
TOSU:TOSH:TOSL, hold the contents of the stack
location
(Figure 5-4). This allows users to implement a software
stack if necessary. After a CALL, RCALL or interrupt
(and ADDULNK and SUBULNK instructions if the
extended instruction set is enabled), the software can
read
TOSU:TOSH:TOSL registers. These values can be
placed on a user-defined software stack. At return time,
the
TOSU:TOSH:TOSL and do a return.
The user must disable the global interrupt enable bits
while accessing the stack to prevent inadvertent stack
corruption.
11111
11110
11101
00011
00010
00001
00000
software
and
the
pointed
writable.
Top-of-Stack Access
pushed
can
to
Stack Pointer
STKPTR<4:0>
A
by
return
value
00010
set
the
of
these
by
STKPTR
DS39775C-page 73
three
reading
values
registers,
register
the
to