Serial downloading, Atmega16(l) – Rainbow Electronics ATmega64L User Manual
Page 265
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265
ATmega16(L)
2466B–09/01
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.
Serial Downloading
Both the Flash and EEPROM memory arrays can be programmed using the serial SPI
bus while RESET is pulled to GND. The serial interface consists of pins SCK, MOSI
(input) and MISO (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 114 on page 266, the pin mapping for SPI programming is listed. Not all parts use
the SPI pins dedicated for the internal SPI interface.
Table 113. Parallel Programming Characteristics, V
CC
= 5 V ± 10%
Symbol
Parameter
Min
Typ
Max
Units
V
PP
Programming Enable Voltage
11.5
12.5
V
I
PP
Programming Enable Current
250
µA
t
DVXH
Data and Control Valid before XTAL1 High
67
ns
t
XLXH
XTAL1 Low to XTAL1 High
200
ns
t
XHXL
XTAL1 Pulse Width High
150
ns
t
XLDX
Data and Control Hold after XTAL1 Low
67
ns
t
XLWL
XTAL1 Low to WR Low
0
ns
t
XLPH
XTAL1 Low to PAGEL high
0
ns
t
PLXH
PAGEL low to XTAL1 high
150
ns
t
BVPH
BS1 Valid before PAGEL High
67
ns
t
PHPL
PAGEL Pulse Width High
150
ns
t
PLBX
BS1 Hold after PAGEL Low
67
ns
t
WLBX
BS2/1 Hold after WR Low
67
ns
t
PLWL
PAGEL Low to WR Low
67
ns
t
BVWL
BS1 Valid to WR Low
67
ns
t
WLWH
WR Pulse Width Low
150
ns
t
WLRL
WR Low to RDY/BSY Low
0
1
µs
t
WLRH
WR Low to RDY/BSY High
3.7
4.5
ms
t
WLRH_CE
WR Low to RDY/BSY High for Chip Erase
7.5
9
ms
t
XLOL
XTAL1 Low to OE Low
0
ns
t
BVDV
BS1 Valid to DATA valid
0
250
ns
t
OLDV
OE Low to DATA Valid
250
ns
t
OHDZ
OE High to DATA Tri-stated
250
ns