t89c51rd2-slscl ATMEL Corporation, t89c51rd2-slscl Datasheet - Page 60

• Manufacturer Part Number: t89c51rd2-slscl
• Description: 0 To 40 Mhz Flash Programmable 8-bit Microcontroller
• Manufacturer: ATMEL Corporation

Functional Description
Figure 23. Bootloader Functional Description
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T89C51RD2
Exernal Host with
Specific Protocol
Communication
On the above diagram, the on-chip bootloader processes are:
•
The purpose of this process is to manage the communication and its protocol between
the on-chip bootloader and a external device. The on-chip ROM implement a serial pro-
tocol (see section Bootloader Protocol). This process translate serial communication
frame (UART) into Flash memory acess (read, write, erase ...).
•
Several Application Program Interface (API) calls are available for use by an application
program to permit selective erasing and programming of Flash pages. All calls are made
through a common interface (API calls), included in the ROM bootloader. The program-
ming functions are selected by setting up the microcontroller’s registers before making a
call to a common entry point (0xFFF0). Results are returned in the registers. The pur-
pose on this process is to translate the registers values into internal Flash Memory
Management.
•
This process manages low level access to Flash memory (performs read and write
access).
ISP Communication
ISP Communication Management
User Call Management
Flash Memory Management
Management
Flash Memory
Management
Flash
Memory
Management (API )
User Call
Application
User
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