DS80C320-ECG+ Maxim Integrated Products, DS80C320-ECG+ Datasheet - Page 19
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DS80C320-ECG+
Manufacturer Part Number
DS80C320-ECG+
Description
IC MCU HI SPEED 25MHZ 44-TQFP
Manufacturer
Maxim Integrated Products
Series
80Cr
Datasheet
1.DS80C323-QND.pdf
(38 pages)
Specifications of DS80C320-ECG+
Core Processor
8051
Core Size
8-Bit
Speed
25MHz
Connectivity
EBI/EMI, SIO, UART/USART
Peripherals
Power-Fail Reset, WDT
Number Of I /o
32
Program Memory Type
ROMless
Ram Size
256 x 8
Voltage - Supply (vcc/vdd)
4.5 V ~ 5.5 V
Oscillator Type
External
Operating Temperature
0°C ~ 70°C
Package / Case
44-TQFP, 44-VQFP
Processor Series
DS80C320
Core
8051
Data Bus Width
8 bit
Program Memory Size
64 KB
Data Ram Size
64 KB
Interface Type
UART
Maximum Clock Frequency
25 MHz
Number Of Programmable I/os
32
Number Of Timers
3
Operating Supply Voltage
4.25 V to 5.5 V
Maximum Operating Temperature
+ 70 C
Mounting Style
SMD/SMT
3rd Party Development Tools
PK51, CA51, A51, ULINK2
Minimum Operating Temperature
0 C
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Eeprom Size
-
Program Memory Size
-
Data Converters
-
Lead Free Status / Rohs Status
Details
Figure 4. Ring Oscillator Startup
TIMED ACCESS PROTECTION
Selected SFR bits are critical to operation, making it desirable to protect against an accidental write
operation. The Timed Access procedure prevents an errant CPU from accidentally altering a bit that
would cause difficulty. The Timed Access procedure requires that the write of a protected bit be preceded
by the following instructions:
By writing an AAh followed by a 55h to the Timed Access register (location C7h), the hardware opens a
three-cycle window that allows software to modify one of the protected bits. If the instruction that seeks
to modify the protected bit is not immediately proceeded by these instructions, the write will not take
effect. The protected bits are:
MOV
MOV
EXIF.0
WDCON.6
WDCON.1
WDCON.0
WDCON.3
DIAGRAM ASSUMES THAT THE OPERATION FOLLOWING STOP REQUIRES LESS THAN 18ms COMPLETE.
0C7h, #0AAh
0C7h, #55h
BGS Bandgap Select
POR Power-on Reset flag
EWT Enable Watchdog
RWT Reset Watchdog
WDIF Watchdog Interrupt Flag
DS80C320/DS80C323 High-Speed/Low-Power Microcontrollers
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