at89lp2052-20xi ATMEL Corporation, at89lp2052-20xi Datasheet - Page 59

• Manufacturer Part Number: at89lp2052-20xi
• Description: At89lp2052 8-bit Microcontroller With 2/4-kbyte Flash
• Manufacturer: ATMEL Corporation

Figure 23-3. Parallel Write Command Sequence
Figure 23-4. Parallel Read Command Sequence
3547H–MICRO–5/07
XTAL1
XTAL1
CS
CS
P1
P1
Figure 23-2. Flash Parallel Programming Device Connections
Note:
While CS is high, the interface is reset to its default state and P1 is tri-stated. CS should be
brought low before the first byte of a command is issued, and should return high only after the
last byte of the command has been strobed.
mand sequence. Command, address, and data bytes are sampled from P1 on the rising edge of
the XTAL1 pulse.
and address bytes are sampled from P1 on the rising edge of the XTAL1 pulse. At the falling
edge of the fourth XTAL1 pulse the device enables P1 to output data. The data remains on P1
until CS is brought high. During reads the parallel programmer should tri-state P1 before the
negative edge of the fourth XTAL1 pulse to avoid bus contention.
AAh
AAh
Sampling of pin P3.1 (RDY/BSY) is optional. During Parallel Programming, P3.1 will be pulled low
while the device is busy. Note that it does not require an external passive pull-up to V
R DY/BSY
Figure 23-4
OPCODE
OPCODE
CS
shows a generic parallel read command sequence. Command
ADDRH
ADDRH
AT89LP2052/LP4052
P3.1
P3.2
X TAL 1
GND
Figure 23-3
ADDRL
ADDRL
AT89LP2052/LP4052
VCC
RST
P1
shows a generic parallel write com-
DATAIN
2.7 to 5.5V
DATAOUT
DATA
V PP
CC
.
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