DSPIC33FJ128MC804-H/ML Microchip Technology, DSPIC33FJ128MC804-H/ML Datasheet - Page 168

• Manufacturer Part Number: DSPIC33FJ128MC804-H/ML
• Description: 16-bit DSC, 128KB Flash, Motor, CAN, DMA, 40 MIPS, NanoWatt 44 QFN 8x8x0.9mm TUB
• Manufacturer: Microchip Technology
• Series: dsPIC™ 33Fr

Specifications of DSPIC33FJ128MC804-H/ML

• Core Processor: dsPIC
• Core Size: 16-Bit
• Speed: 20 MIPS
• Connectivity: CAN, I²C, IrDA, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, DMA, Motor Control PWM, QEI, POR, PWM, WDT
• Number Of I /o: 35
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 9x10b/12b, D/A 6x16b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 140°C
• Package / Case: 44-QFN
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

dsPIC33FJ32MC302/304, dsPIC33FJ64MCX02/X04 AND dsPIC33FJ128MCX02/X04
11.6.3
Because peripheral remapping can be changed during
run time, some restrictions on peripheral remapping
are needed to prevent accidental configuration
changes. dsPIC33F devices include three features to
prevent alterations to the peripheral map:
• Control register lock sequence
• Continuous state monitoring
• Configuration bit pin select lock
11.6.3.1
Under normal operation, writes to the RPINRx and
RPORx registers are not allowed. Attempted writes
appear to execute normally, but the contents of the reg-
isters remain unchanged. To change these registers,
they must be unlocked in hardware. The register lock is
controlled by the IOLOCK bit (OSCCON<6>). Setting
IOLOCK prevents writes to the control registers;
clearing IOLOCK allows writes.
To set or clear the IOLOCK bit, a specific command
sequence must be executed:
1.
2.
3.
Unlike the similar sequence with the oscillator’s LOCK
bit, IOLOCK remains in one state until changed. This
allows all of the peripheral pin selects to be configured
with a single unlock sequence followed by an update to
all control registers, then locked with a second lock
sequence.
DS70291E-page 168
Note:
Write 0x46 to OSCCON<7:0>.
Write 0x57 to OSCCON<7:0>.
Clear (or set) the IOLOCK bit as a single
operation.
CONTROLLING CONFIGURATION
CHANGES
MPLAB
language functions for unlocking the
OSCCON register:
See MPLAB IDE Help for more
information.
Control Register Lock
__builtin_write_OSCCONL(value)
__builtin_write_OSCCONH(value)
®
C30
provides
built-in
C
11.6.3.2
In addition to being protected from direct writes, the
contents of the RPINRx and RPORx registers are
constantly monitored in hardware by shadow registers.
If an unexpected change in any of the registers occurs
(such as cell disturbances caused by ESD or other
external events), a configuration mismatch Reset is
triggered.
11.6.3.3
As an additional level of safety, the device can be
configured to prevent more than one write session to
the RPINRx and RPORx registers. The IOL1WAY Con-
figuration bit (FOSC<5>) blocks the IOLOCK bit from
being cleared after it has been set once. If IOLOCK
remains set, the register unlock procedure does not
execute, and the peripheral pin select control registers
cannot be written to. The only way to clear the bit and
re-enable peripheral remapping is to perform a device
Reset.
In the default (unprogrammed) state, IOL1WAY is set,
restricting users to one write session. Programming
IOL1WAY allows user applications unlimited access
(with the proper use of the unlock sequence) to the
peripheral pin select registers.
Continuous State Monitoring
Configuration Bit Pin Select Lock
© 2011 Microchip Technology Inc.