ATMEGA325-16AJ ATMEL [ATMEL Corporation], ATMEGA325-16AJ Datasheet - Page 281
ATMEGA325-16AJ
Manufacturer Part Number
ATMEGA325-16AJ
Description
8-bit Microcontroller with In-System Programmable Flash
Manufacturer
ATMEL [ATMEL Corporation]
Datasheet
1.ATMEGA325-16AJ.pdf
(347 pages)
- Current page: 281 of 347
- Download datasheet (3Mb)
Flash Data Byte Register
2570A–AVR–09/04
Figure 125. State Machine Sequence for Changing/Reading the Data Word
The Flash Data Byte Register provides an efficient way to load the entire Flash page
buffer before executing Page Write, or to read out/verify the content of the Flash. A state
machine sets up the control signals to the Flash and senses the strobe signals from the
Flash, thus only the data words need to be shifted in/out.
The Flash Data Byte Register actually consists of the 8-bit scan chain and a 8-bit tempo-
rary register. During page load, the Update-DR state copies the content of the scan
chain over to the temporary register and initiates a write sequence that within 11 TCK
cycles loads the content of the temporary register into the Flash page buffer. The AVR
automatically alternates between writing the low and the high byte for each new Update-
DR state, starting with the low byte for the first Update-DR encountered after entering
the PROG_PAGELOAD command. The Program Counter is pre-incremented before
writing the low byte, except for the first written byte. This ensures that the first data is
written to the address set up by PROG_COMMANDS, and loading the last location in
the page buffer does not make the Program Counter increment into the next page.
During Page Read, the content of the selected Flash byte is captured into the Flash
Data Byte Register during the Capture-DR state. The AVR automatically alternates
between reading the low and the high byte for each new Capture-DR state, starting with
the low byte for the first Capture-DR encountered after entering the PROG_PAGEREAD
command. The Program Counter is post-incremented after reading each high byte,
1
0
Test-Logic-Reset
Run-Test/Idle
0
1
1
0
ATmega325/3250/645/6450
Select-DR Scan
Capture-DR
Update-DR
Pause-DR
Exit1-DR
Exit2-DR
Shift-DR
1
0
0
1
0
1
1
0
1
1
0
0
1
0
Select-IR Scan
Capture-IR
Update-IR
Pause-IR
Exit1-IR
Exit2-IR
Shift-IR
1
0
0
1
0
1
1
0
1
1
0
0
281
Related parts for ATMEGA325-16AJ
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
Atmel Corporation
Datasheet:
Part Number:
Description:
Manufacturer:
ATMEL Corporation
Datasheet:
Part Number:
Description:
IC AVR MCU 2.4GHZ XCEIVER 64QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU ATMEGA644/AT86RF230 40-DIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
BUNDLE ATMEGA644P/AT86RF230 QFN
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
BUNDLE ATMEGA644P/AT86RF230 TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU ATMEGA1281/AT86RF230 64-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU ATMEGA1280/AT86RF230 100TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
BUNDLE ATMEGA1280/AT86RF100-TQFP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
MCU, 8BIT, AVR, 16K FLASH, 28PDIP
Manufacturer:
Atmel
Datasheet:
Part Number:
Description:
Microcontroller Modules MCU CARD BIGAVR6 100P W/ ATMEGA2560
Manufacturer:
mikroElektronika