PIC18F86J50T-I/PT Microchip Technology, PIC18F86J50T-I/PT Datasheet - Page 92

• 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

PIC18F87J50 FAMILY
5.4.3.2
In addition to the INDF operand, each FSR register pair
also has four additional indirect operands. Like INDF,
these are “virtual” registers that cannot be indirectly
read or written to. Accessing these registers actually
accesses the associated FSR register pair, but also
performs a specific action on its stored value. They are:
• POSTDEC: accesses the FSR value, then
• POSTINC: accesses the FSR value, then
• PREINC: increments the FSR value by ‘1’, then
• PLUSW: adds the signed value of the W register
In this context, accessing an INDF register uses the
value in the FSR registers without changing them.
Similarly, accessing a PLUSW register gives the FSR
value offset by the value in the W register; neither value
is actually changed in the operation. Accessing the
other virtual registers changes the value of the FSR
registers.
Operations on the FSRs with POSTDEC, POSTINC
and PREINC affect the entire register pair; that is, roll-
overs of the FSRnL register from FFh to 00h carry over
to the FSRnH register. On the other hand, results of
these operations do not change the value of any flags
in the STATUS register (e.g., Z, N, OV, etc.).
The PLUSW register can be used to implement a form
of Indexed Addressing in the data memory space. By
manipulating the value in the W register, users can
reach addresses that are fixed offsets from pointer
addresses. In some applications, this can be used to
implement some powerful program control structure,
such as software stacks, inside of data memory.
DS39775C-page 92
automatically decrements it by ‘1’ afterwards
automatically increments it by ‘1’ afterwards
uses it in the operation
(range of -127 to 128) to that of the FSR and uses
the new value in the operation
FSR Registers and POSTINC,
POSTDEC, PREINC and PLUSW
5.4.3.3
Indirect Addressing operations that target other FSRs
or virtual registers represent special cases. For exam-
ple, using an FSR to point to one of the virtual registers
will not result in successful operations. As a specific
case, assume that FSR0H:FSR0L contains FE7h, the
address of INDF1. Attempts to read the value of the
INDF1, using INDF0 as an operand, will return 00h.
Attempts to write to INDF1, using INDF0 as the
operand, will result in a NOP.
On the other hand, using the virtual registers to write to
an FSR pair may not occur as planned. In these cases,
the value will be written to the FSR pair but without any
incrementing or decrementing. Thus, writing to INDF2
or POSTDEC2 will write the same value to the
FSR2H:FSR2L.
Since the FSRs are physical registers mapped in the
SFR space, they can be manipulated through all direct
operations. Users should proceed cautiously when
working on these registers, particularly if their code
uses Indirect Addressing.
Similarly, operations by Indirect Addressing are gener-
ally permitted on all other SFRs. Users should exercise
the appropriate caution that they do not inadvertently
change settings that might affect the operation of the
device.
5.5
The operation of program memory is unaffected by the
use of the extended instruction set.
Enabling the extended instruction set adds five
additional two-word commands to the existing PIC18
instruction set: ADDFSR, CALLW, MOVSF, MOVSS and
SUBFSR. These instructions are executed as described
in Section 5.2.4 “Two-Word Instructions”.
Program Memory and the
Extended Instruction Set
Operations by FSRs on FSRs
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