atmega32u4-16mu ATMEL Corporation, atmega32u4-16mu Datasheet - Page 376

• Manufacturer Part Number: atmega32u4-16mu
• Description: Atmega32u4 8-bit Avr Microcontroller With 32k Bytes Of Isp Flash And Usb Controller
• Manufacturer: ATMEL Corporation

29.6.9
29.6.10
29.6.11
376
ATmega32U4
Programming the Fuse High Bits
Programming the Extended Fuse Bits
Programming the Lock Bits
The algorithm for programming the Fuse High bits is as follows (refer to
Flash” on page 372
The algorithm for programming the Extended Fuse bits is as follows (refer to
Flash” on page 372
Figure 29-5. Programming the FUSES Waveforms
The algorithm for programming the Lock bits is as follows (refer to
page 372
The Lock bits can only be cleared by executing Chip Erase.
1. A: Load Command “0100 0000”.
2. C: Load Data Low Byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
3. Set BS2, BS1 to “01”. This selects high data byte.
4. Give WR a negative pulse and wait for RDY/BSY to go high.
5. Set BS2, BS1 to “00”. This selects low data byte.
1. 1. A: Load Command “0100 0000”.
2. 2. C: Load Data Low Byte. Bit n = “0” programs and bit n = “1” erases the Fuse bit.
3. 3. Set BS2, BS1 to “10”. This selects extended data byte.
4. 4. Give WR a negative pulse and wait for RDY/BSY to go high.
5. 5. Set BS2, BS1 to “00”. This selects low data byte.
1. A: Load Command “0010 0000”.
2. C: Load Data Low Byte. Bit n = “0” programs the Lock bit. If LB mode 3 is programmed
3. Give WR a negative pulse and wait for RDY/BSY to go high.
RESET +12V
(LB1 and LB2 is programmed), it is not possible to program the Boot Lock bits by any
External Programming mode.
RDY/BSY
PAGEL
XTAL1
DATA
for details on Command and Data loading):
XA1
XA0
BS1
BS2
WR
OE
0x40
A
for details on Command and Data loading):
for details on Command and Data loading):
DATA
C
Write Fuse Low byte
XX
0x40
A
DATA
C
Write Fuse high byte
XX
0x40
“Programming the Flash” on
A
DATA
C
Write Extended Fuse byte
“Programming the
XX
“Programming the
7766A–AVR–03/08