DS89C450-QNL+ Maxim Integrated Products, DS89C450-QNL+ Datasheet - Page 22

• Manufacturer Part Number: DS89C450-QNL+
• Description: IC MCU FLASH 64KB 33MHZ 44-PLCC
• Manufacturer: Maxim Integrated Products
• Series: 89Cr

Specifications of DS89C450-QNL+

• Core Processor: 8051
• Core Size: 8-Bit
• Speed: 33MHz
• Connectivity: EBI/EMI, SIO, UART/USART
• Peripherals: Power-Fail Reset, WDT
• Number Of I /o: 32
• Program Memory Size: 64KB (64K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-LCC, 44-PLCC
• Processor Series: 89C
• Core: 8051
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Maximum Clock Frequency: 33 MHz
• Number Of Programmable I/os: 32
• Number Of Timers: 3
• Operating Supply Voltage: 5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: PK51, CA51, A51, ULINK2
• Development Tools By Supplier: DS89C450-K00
• Minimum Operating Temperature: - 40 C
• Interface Type: UART
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

fetch that takes four clocks. Page mode 1 is the only external addressing mode where the CPU does not require
stalls for external memory access, but page misses result in reduced external access performance.
On-Chip Program Memory
The processor can fetch the entire on-chip program memory range automatically. By default, the reset routines and
all interrupt vectors are located in the lower 128 bytes of the on-chip program memory.
On-chip program memory is logically divided into pairs of 8kB, 16kB, or 32kB flash memory banks to support in-
application programming. The upper block of the on-chip program memory is designed to be programmed in-
application with the standard 5V V
memory loader. It can also be programmed in standard flash or EPROM programmers. The DS89C430
incorporates a memory management unit (MMU) and other hardware to support any of the three programming
methods. The MMU controls program and data memory access, and provides sequencing and timing controls for
programming of the on-chip program memory. A separate security flash block supports a three-level lock, a 64-byte
encryption array, and other flash options.
Security Features
The DS89C430 incorporates a 64-byte encryption array, allowing the user to verify program codes while viewing
the data in encrypted form. The encryption array is implemented in a security flash memory block that has the
same electrical and timing characteristics as the on-chip program memory. Once the encryption array is
programmed to non-FFh, the data presented in the verify mode is encrypted. Each byte of data is XNORed with a
byte in the encryption array during verification.
A three-level lock restricts viewing of the internal program and data memory contents. By programming the three
lock bits, the user can select a level of security as specified in
than those in a traditional 8051 microcontroller, and should not be used while executing external code.
Once a security level is selected and programmed, the setting of the lock bits remains. Only a mass erase can
erase these bits and allow reprogramming the security level to a less restricted protection.
Table 3. Flash Memory Lock Bits
The DS89C430 provides user-selectable options that must be set before beginning software execution. The option
control register uses flash bits rather than SFRs, and is individually erasable and programmable as a byte-wide
register. Bit 3 of this register is defined as the watchdog POR. Setting this bit to 1 disables the watchdog reset
function on power-up. Clearing this bit to 0 enables the watchdog reset function automatically. Other bits of this
register are undefined and are at logic 1 when read. The value of this register can be read at address FCh in
parallel programming mode or executing a verify-option-control register instruction in ROM loader mode or in-
application programming mode.
LEVEL
1
2
3
4
LB1
X
X
1
0
LB2
X
1
1
0
CC
LB3
supply under the control of the user software or by using a built-in program
1
1
1
0
No program lock. Encrypted verify if encryption array is programmed. Do
not execute external program code while operating at this security level.
Prevent MOVC in external memory from reading program code in internal
memory. EA is sampled and latched on reset. Allow no further parallel or
program memory loader programming. Do not execute external program
code while operating at this security level.
Level 2 plus no verify operation. Also prevent MOVX in external memory
from reading internal SRAM. Do not execute external program code while
operating at this security level.
Level 3 plus no external execution.
DS89C430/DS89C450 Ultra-High-Speed Flash Microcontrollers
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Table
3. The protection levels function differently
PROTECTION