M306N4FGTFP Renesas Electronics America, M306N4FGTFP Datasheet - Page 98

• Manufacturer Part Number: M306N4FGTFP
• Description: IC M16C MCU FLASH 100QFP
• Manufacturer: Renesas Electronics America
• Series: M16C™ M16C/6Nr

Specifications of M306N4FGTFP

• Core Processor: M16C/60
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: CAN, I²C, IEBus, SIO, UART/USART
• Peripherals: DMA, WDT
• Number Of I /o: 85
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 10K x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 26x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

M16C/6N Group (M16C/6N4)
Rev.2.40
REJ09B0009-0240
9. Protection
In the event that a program runs out of control, this function protects the important registers so that they will
not be rewritten easily.
Figure 9.1 shows the PRCR Register. The registers protected by the PRCR register are listed below.
Set the PRC2 bit to 1 (write enabled) and then write to given address, and the PRC2 bit will be set to 0 (write
protected). The registers protected by the PRC2 bit should be changed in the next instruction after setting
the PRC2 bit to 1. Make sure no interrupts or DMA transfers will occur between the instruction in which the
PRC2 bit is set to 1 and the next instruction. Bits PRC0 and PRC1 are not automatically set to 0 by writing
to given address. They can only be set to 0 in a program.
Figure 9.1 PRCR Register
• Registers protected by the PRC0 bit: Registers CM0, CM1, CM2, PLC0, PCLKR, and CCLKR
• Registers protected by the PRC1 bit: Registers PM0, PM1, PM2, TB2SC, INVC0, and INVC1
• Registers protected by the PRC2 bit: Registers PD7, PD9, and S3C
Protect Register
NOTE:
b7
1. The PRC2 bit is set to 0 by writing to given address after setting it to 1. Other bits are not set to 0 by writing to
Apr 14, 2006
b6
given address, and must therefore be set in a program.
0 0 0
b5
b4
b3
b2
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b1
b0
Bit Symbol
(b5-b3)
(b7-b6)
PRC0
PRC1
PRC2
Symbol
PRCR
-
-
Protect bit 0
Protect bit 1
Protect bit 2
Reserved bits
Nothing is assigned. If necessary, set to 0.
When read, the content is undefined.
Address
000Ah
Bit Name
After Reset
XX000000b
Writing to registers CM0, CM1,
CM2, PLC0, PCLKR, CCLKR
is enabled
Writing to registers PM0, PM1,
PM2, TB2SC, INVC0, INVC1
is enabled
Writing to registers PD7, PD9,
S3C is enabled
Set to 0
0 : Write protected
1 : Write enabled
0 : Write protected
1 : Write enabled
0 : Write protected
1 : Write enabled
Function
(1)
9. Protection
RW
RW
RW
RW
RW
-