AT89LP51ED2-20MU Atmel, AT89LP51ED2-20MU Datasheet - Page 192

• 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

Table 24-6.
24.4
24.4.1
192
Mode
1
2
3
4
In-Application Programming (IAP)
Program Lock Bits (by address)
AT89LP51RD2/ED2/ID2 Preliminary
API Call Description
Security Protection Modes
00h
FFh
00h
00h
00h
The AT89LP51RD2/ED2/ID2 supports In-Application Programming (IAP), allowing the program
memory to be modified during execution. IAP can be used to modify the user application on the
fly or to use program memory for nonvolatile data storage. The AT89LP51RD2/ED2/ID2
includes a Flash Application Programming Interface (API) as part of the bootloader ROM code.
The Flash API is the preferred way to program the Flash memory from the application code.
Advanced users looking to write their own low-level routines should refer to
page
The In-Application Programming (IAP) feature allows reprogramming a microcontroller on-chip
Flash memory without removing it from the system and while the embedded application is run-
ning. The user application can call Flash Application Programming Interface (API) routines
allowing IAP. These Flash API are also executed by the bootloader.
To call the corresponding API, the user may use a set of routines which can be linked with the
application. Example of Flash_api routines are available on the Atmel web site on the software
application note:
C Flash Drivers for the AT89C51RD2/ED2
The API calls description and arguments are shown in
The application selects an API by setting R1, ACC, DPTR0 and DPTR1 registers. All calls are
made through a common interface “USER_CALL” at the address FFF0h. The jump to the
USER_CALL must be done by an LCALL instruction in order to be able to return to the applica-
tion. Before jumping to USER_CALL, the bit ENBOOT in AUXR1 register must be set to map the
ROM code into the address space.
Flash API calls have the following constraints:
• The interrupts are not disabled by the bootloader. Interrupts must be disabled by the user
• The user must feed the hardware watchdog before launching a Flash operation.
• The API call requires a minimum of two free stack bytes
01h
FFh
FFh
00h
00h
prior to calling USER_CALL, then re-enabled when returning.
194.
02h
FFh
FFh
FFh
00h
Protection Mode
No program lock features
Further programming of the Flash is disabled
Further programming of the Flash is disabled and verify (read) is also disabled
Further programming of the Flash is disabled and verify (read) is also disabled;
External execution above 32K when BMS = 1 is disabled
Table
24-7.
Section 24.4.2 on
3714A–MICRO–7/11