AT89LP51ED2-20MU Atmel, AT89LP51ED2-20MU Datasheet - Page 187

• Manufacturer Part Number: AT89LP51ED2-20MU
• Description: 8-bit Microcontrollers - MCU 64KB 20MHz 2.4V-5.5V
• Manufacturer: Atmel

Specifications of AT89LP51ED2-20MU

• Rohs: yes
• Core: 8051
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 20 MHz
• Program Memory Size: 64 KB
• Data Ram Size: 256 B
• On-chip Adc: Yes
• Operating Supply Voltage: 2.4 V to 5.5 V
• Operating Temperature Range: - 40 C to + 85 C
• Package / Case: VQFN-44
• Mounting Style: SMD/SMT
• Data Rom Size: 4 KB
• Interface Type: 2-Wire, SPI, UART
• Number Of Programmable I/os: 36
• Number Of Timers: 3
• Processor Series: AT89x
• Program Memory Type: Flash
• Factory Pack Quantity: 360

24. Flash Memory Programming
3714A–MICRO–7/11
The Atmel AT89LP51RD2/ED2/ID2 microcontroller features 64K bytes of on-chip In-System
Programmable Flash program memory and 4K bytes of EEPROM data memory. In-System Pro-
gramming allows programming and reprogramming of the microcontroller positioned inside the
end system. The programmer communicates serially with the AT89LP51RD2/ED2/ID2 micro-
controller, reprogramming all nonvolatile memories on the chip. In-System Programming
eliminates the need for physical removal of the chips from the system. This will save time and
money, both during development in the lab, and when updating the software or parameters in
the field. The AT89LP51RD2/ED2/ID2 provides the following programming interfaces:
None of the programming interfaces require an external dedicated programming voltage. The
necessary high programming voltage is generated on-chip using the standard V
microcontroller.
Note:
• High-Speed, four-wire SPI-based programming interface (ISP)
• 12-pin parallel programming interface (PRL)
• ROM-based UART serial bootloader (BOOT)
• User-defined bootloader and/or In-Application Programming (IAP)
This synchronous hardware interface programs the device while it is in reset and therefore,
does not require the CPU to be operational, i.e. no clock is required except the SPI serial
clock. This interface can be used both in-system and in a stand-alone programmer, and has
full access to all nonvolatile memory resources. This interface is compatible with the Atmel
AT89LP ISP Studio software. See
for more information.
This interface is a submode of the SPI interface that allows data to be read/written one 8-bit
byte at a time instead of serially 1-bit at a time. This interface is intended only for stand-alone
programmers. An 87C51-compatible parallel interface is not available. See
“Physical Interface” on page 215
When using this 2-pin asynchronous interface, the device runs a default software bootloader
from an on-chip ROM. The system clock must be operational and will limit the speed at which
the interface functions. This interface is intended for in-system use. It has full access to the
Flash code memory and EEPROM data memory, but does not have access to all
configuration options. This interface is compatible with the Atmel FLIP software. See
24.5 “Bootloader” on page 200
The ROM bootloader can call a user-defined bootloader located within the code memory
instead of the default UART bootloader. The user is free to use any available interface to
program the device. The ROM also contains an application programming interface (API) that
implements the low-level routines necessary to perform in-application programming (IAP). It
is recommended that users employ these functions instead of writing their own low-level
routines. Advanced users may wish to implement their own routines in some cases. See
Section 24.4 “In-Application Programming (IAP)” on page
In this document the term Bootloader, or BOOT, is used to when referring to the UART-based
ROM bootloader and In-System Programming, or ISP, is used with reference to the SPI-based
interface. This is different from AT89C51RD2/ED2/ID2 where ISP also referred to the bootloader
(as no SPI programming interface was present). However, it should be noted that both interfaces
are perfectly capable of performing in-system programming, i.e programming the device when it is
already mounted in the final end-user system.
AT89LP51RD2/ED2/ID2 Preliminary
for more information.
for more information.
Section 24.6 “In-System Programming (ISP)” on page 215
192.
Section 24.6.1
DD
pin of the
Section
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