AT89C5132 Atmel Corporation, AT89C5132 Datasheet - Page 19

• Manufacturer Part Number: AT89C5132
• Manufacturer: Atmel Corporation

Specifications of AT89C5132

• Flash (kbytes): 64 Kbytes
• Max. Operating Frequency: 20 MHz
• Cpu: 8051-12C
• Max I/o Pins: 44
• Usb Transceiver: 1
• Usb Speed: Full Speed
• Usb Interface: Device
• Spi: 1
• Uart: 1
• Adc Channels: 2
• Adc Resolution (bits): 10
• Adc Speed (ksps): 22.7
• Sram (kbytes): 2.25
• Self Program Memory: API
• Operating Voltage (vcc): 2.7 to 3.6
• Timers: 2
• Isp: UART/USB
• Watchdog: Yes

7.3
7.3.1
7.3.2
7.3.3
Figure 7-3.
4173E–USB–09/07
Boot Memory Execution
Software Boot Mapping
Hardware Condition Boot Mapping
Programmed Condition Boot Mapping
Hardware Boot Process Algorithm
As internal C51 code space is limited to 64K Bytes, some mechanisms are implemented to allow
boot memory to be mapped in the code space for execution at addresses from F000h to FFFFh.
The boot memory is enabled by setting the ENBOOT bit in AUXR1 (see
ways to set this bit are detailed in the following sections.
The software way to set ENBOOT consists in writing to AUXR1 from the user’s software. This
enables bootloader or API routines execution.
The hardware condition is based on the ISP pin. When driving this pin to low level, the chip reset
sets ENBOOT and forces the reset vector to F000h instead of 0000h in order to execute the
bootloader software.
As shown in Figure 7-3, the hardware condition always allows in-system recovery when user’s
memory has been corrupted.
The programmed condition is based on the Bootloader Jump Bit (BLJB) in HSB. As shown in
Figure 7-3, when this bit is programmed (by hardware or software programming mode), the chip
resets ENBOOT and forces the reset vector to F000h instead of 0000h, in order to execute the
bootloader software.
The software process (bootloader) is detailed in the AT89C5132 Bootloader datasheet.
Application
Standard Init
ENBOOT = 0
FCON = F0h
PC = 0000h
User’s
Prog Cond Init
Boot Loader
ENBOOT = 1
Hard Cond?
Prog Cond?
FCON = F0h
PC = F000h
BLJB = P?
Atmel’s
RESET
ISP = L?
Hard Cond Init
ENBOOT = 1
FCON = 00h
PC = F000h
AT89C5132
Table
6). The three
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