PIC18F2525-I/SP Microchip Technology, PIC18F2525-I/SP Datasheet - Page 207

• Manufacturer Part Number: PIC18F2525-I/SP
• Description: IC MCU FLASH 24KX16 28-DIP
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F2525-I/SP

• Program Memory Type: FLASH
• Program Memory Size: 48KB (24K x 16)
• Package / Case: 28-DIP (0.300", 7.62mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, HLVD, POR, PWM, WDT
• Number Of I /o: 25
• Eeprom Size: 1K x 8
• Ram Size: 3.8K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 10x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 3986 B
• Interface Type: SPI/I2C/EUSART
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 25
• Number Of Timers: 4
• Operating Supply Voltage: 4.2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, ICE4000, DM163022, DV164136
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10-ch x 10-bit
• Package: 28SPDIP
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 40 MHz
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: I3DB18F4620 - BOARD DAUGHTER ICEPIC3DVA18XP280 - DEVICE ADAPTER 18F2220 PDIP 28LD
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

18.1
The BRG is a dedicated 8-bit or 16-bit generator that
supports both the Asynchronous and Synchronous
modes of the EUSART. By default, the BRG operates
in 8-bit mode; setting the BRG16 bit (BAUDCON<3>)
selects 16-bit mode.
The SPBRGH:SPBRG register pair controls the period
of a free-running timer. In Asynchronous mode, bits,
BRGH (TXSTA<2>) and BRG16 (BAUDCON<3>), also
control the baud rate. In Synchronous mode, BRGH is
ignored. Table 18-1 shows the formula for computation
of the baud rate for different EUSART modes which
only apply in Master mode (internally generated clock).
Given the desired baud rate and F
integer value for the SPBRGH:SPBRG registers can be
calculated using the formulas in Table 18-1. From this,
the error in baud rate can be determined. An example
calculation is shown in Example 18-1. Typical baud
rates and error values for the various Asynchronous
modes are shown in Table 18-2. It may be advantageous
to use the high baud rate (BRGH = 1) or the 16-bit BRG
to reduce the baud rate error, or achieve a slow baud
rate for a fast oscillator frequency.
TABLE 18-1:
© 2008 Microchip Technology Inc.
Legend: x = Don’t care, n = value of SPBRGH:SPBRG register pair
SYNC
0
0
0
0
1
1
Baud Rate Generator (BRG)
Configuration Bits
BAUD RATE FORMULAS
BRG16
0
0
1
1
0
1
BRGH
0
1
0
1
x
x
OSC
, the nearest
PIC18F2525/2620/4525/4620
BRG/EUSART Mode
16-bit/Asynchronous
16-bit/Asynchronous
16-bit/Synchronous
8-bit/Asynchronous
8-bit/Asynchronous
8-bit/Synchronous
Writing any value (even the same value) to the
SPBRGH:SPBRG registers immediately reloads the
BRG timer. This may corrupt a transmission or recep-
tion already in progress. This ensures the BRG does
not wait for a timer overflow before outputting the new
baud rate.
18.1.1
The device clock is used to generate the desired baud
rate. When one of the power-managed modes is
entered, the new clock source may be operating at a
different frequency. This may require an adjustment to
the value in the SPBRG register pair.
18.1.2
The data on the RX pin is sampled three times by a
majority detect circuit to determine if a high or a low
level is present at the RX pin when SYNC is clear or
when BRG16 and BRGH are both not set. The data on
the RX pin is sampled once when SYNC is set or when
BRGH16 and BRGH are both set.
OPERATION IN POWER-MANAGED
MODES
SAMPLING
Baud Rate Formula
F
F
F
OSC
OSC
OSC
/[64 (n + 1)]
/[16 (n + 1)]
/[4 (n + 1)]
DS39626E-page 205