PIC24FJ32GA104-I/PT Microchip Technology, PIC24FJ32GA104-I/PT Datasheet - Page 202

• Manufacturer Part Number: PIC24FJ32GA104-I/PT
• Description: 16-bit, 16 MIPS, 32KB Flash, 8KB RAM, Nanowatt XLP 44 TQFP 10x10x1mm TRAY
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 24Fr

Specifications of PIC24FJ32GA104-I/PT

• Core Processor: PIC
• Core Size: 16-Bit
• Speed: 32MHz
• Connectivity: I²C, IrDA, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 35
• Program Memory Size: 32KB (11K x 24)
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 3.6 V
• Data Converters: A/D 13x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 876-1004 - PIC24 BREAKOUT BOARD
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PIC24FJ64GA104 FAMILY
19.2
The RTCC module registers are organized into three
categories:
• RTCC Control Registers
• RTCC Value Registers
• Alarm Value Registers
19.2.1
To limit the register interface, the RTCC Timer and
Alarm
corresponding register pointers. The RTCC Value
register window (RTCVALH and RTCVALL) uses the
RTCPTR bits (RCFGCAL<9:8>) to select the desired
Timer register pair (see Table 19-1).
By writing to the RTCVALH byte, the RTCC Pointer
value (the RTCPTR<1:0> bits) decrements by one until
they reach ‘00’. Once they reach ‘00’, the MINUTES
and SECONDS value will be accessible through
RTCVALH and RTCVALL until the pointer value is
manually changed.
TABLE 19-1:
The Alarm Value register window (ALRMVALH and
ALRMVALL)
(ALCFGRPT<9:8>) to select the desired Alarm register
pair (see Table 19-2).
By writing to the ALRMVALH byte, the Alarm Pointer
value (ALRMPTR<1:0> bits) decrements by one until
they reach ‘00’. Once they reach ‘00’, the ALRMMIN
and ALRMSEC value will be accessible through
ALRMVALH and ALRMVALL until the pointer value is
manually changed.
EXAMPLE 19-1:
DS39951C-page 202
RTCPTR<1:0>
asm volatile(“push w7”);
asm volatile(“push w8”);
asm volatile(“disi #5”);
asm volatile(“mov #0x55, w7”);
asm volatile(“mov w7, _NVMKEY”);
asm volatile(“mov #0xAA, w8”);
asm volatile(“mov w8, _NVMKEY”);
asm volatile(“bset _RCFGCAL, #13”);
asm volatile(“pop w8”);
asm volatile(“pop w7”);
00
01
10
11
Time
RTCC Module Registers
REGISTER MAPPING
registers
uses
RTCVAL<15:8>
RTCVAL REGISTER MAPPING
RTCC Value Register Window
WEEKDAY
MINUTES
MONTH
SETTING THE RTCWREN BIT
—
the
are
accessed
ALRMPTR
RTCVAL<7:0>
SECONDS
HOURS
YEAR
DAY
through
bits
//set the RTCWREN bit
TABLE 19-2:
Considering that the 16-bit core does not distinguish
between 8-bit and 16-bit read operations, the user must
be aware that when reading either the ALRMVALH or
ALRMVALL bytes, the ALRMPTR<1:0> value will be
decremented. The same applies to the RTCVALH or
RTCVALL bytes with the RTCPTR<1:0> being
decremented.
19.2.2
To perform a write to any of the RTCC Timer registers,
the RTCWREN bit (RCFGCAL<13>) must be set (refer
to Example 19-1).
19.2.3
The clock source for the RTCC module can be selected
using the Flash Configuration bit, RTCOSC (CW4<5>).
When the bit is set to ‘1’, the Secondary Oscillator
(SOSC) is used as the reference clock, and when the
bit is ‘0’, LPRC is used as the reference clock.
ALRMPTR
Note:
Note:
<1:0>
00
01
10
11
This only applies to read operations and
not write operations.
WRITE LOCK
To avoid accidental writes to the timer, it is
recommended that the RTCWREN bit
(RCFGCAL<13>) is kept clear at any
other time. For the RTCWREN bit to be
set, there is only one instruction cycle time
window allowed between the 55h/AA
sequence and the setting of RTCWREN;
therefore, it is recommended that code
follow the procedure in Example 19-1.
SELECTING RTCC CLOCK SOURCE
ALRMVAL<15:8> ALRMVAL<7:0>
ALRMVAL REGISTER
MAPPING
Alarm Value Register Window
ALRMMNTH
ALRMMIN
ALRMWD
 2010 Microchip Technology Inc.
—
ALRMSEC
ALRMDAY
ALRMHR
—