Datasheet

Table Of Contents
338
ATmega640/V-1280/V-1281/V-2560/V-2561/V [DATASHEET]
2549Q–AVR–02/2014
Notes: 1. t
WLRH
is valid for the Write Flash, Write EEPROM, Write Fuse bits and Write Lock bits commands.
2. t
WLRH_CE
is valid for the Chip Erase command.
30.8 Serial Downloading
Both the Flash and EEPROM memory arrays can be programmed using a serial programming bus while RESET is
pulled to GND. The serial programming interface consists of pins SCK, PDI (input) and PDO (output). After RESET
is set low, the Programming Enable instruction needs to be executed first before program/erase operations can be
executed. NOTE, in Table 30-15 on page 339, the pin mapping for serial programming is listed. Not all packages
use the SPI pins dedicated for the internal Serial Peripheral Interface - SPI.
Table 30-14. Parallel Programming Characteristics, V
CC
= 5V ±10%
Symbol Parameter Min Typ Max Units
V
PP
Programming Enable Voltage 11.5 12.5 V
I
PP
Programming Enable Current 250 A
t
DVXH
Data and Control Valid before XTAL1 High 67
ns
t
XLXH
XTAL1 Low to XTAL1 High 200
t
XHXL
XTAL1 Pulse Width High 150
t
XLDX
Data and Control Hold after XTAL1 Low 67
t
XLWL
XTAL1 Low to WR Low 0
t
XLPH
XTAL1 Low to PAGEL high 0
t
PLXH
PAGEL low to XTAL1 high 150
t
BVPH
BS1 Valid before PAGEL High 67
t
PHPL
PAGEL Pulse Width High 150
t
PLBX
BS1 Hold after PAGEL Low 67
t
WLBX
BS2/1 Hold after WR Low 67
t
PLWL
PAGEL Low to WR Low 67
t
BVWL
BS2/1 Valid to WR Low 67
t
WLWH
WR Pulse Width Low 150
t
WLRL
WR Low to RDY/BSY Low 0 1 s
t
WLRH
WR Low to RDY/BSY High
(1)
3.7 4.5
ms
t
WLRH_CE
WR Low to RDY/BSY High for Chip Erase
(2)
7.5 9
t
XLOL
XTAL1 Low to OE Low 0
ns
t
BVDV
BS1 Valid to DATA valid 0 250
t
OLDV
OE Low to DATA Valid 250
t
OHDZ
OE High to DATA Tri-stated 250