參數(shù)資料
型號: DS87C520-MCL
廠商: DALLAS SEMICONDUCTOR
元件分類: Microcontroller
英文描述: 8-BIT, OTPROM, MICROCONTROLLER, PDIP40
封裝: 0.600 INCH, PLASTIC, DIP-40
文件頁數(shù): 4/42頁
文件大?。?/td> 832K
代理商: DS87C520-MCL
DS87C520/DS83C520
12 of 42
DATA MEMORY CYCLE STRETCH VALUES Table 4
CKCON.2-0
RD
OR WR STROBE
STROBE WIDTH TIME
M2
M1
M0
MEMORY CYCLES
WIDTH IN CLOCKS
@ 33 MHz
0
2 (forced internal)
2
60 ns
0
1
3 (default external)
4
121 ns
0
1
0
4
8
242 ns
0
1
5
12
364 ns
1
0
6
16
485 ns
1
0
1
7
20
606 ns
1
0
8
24
727 ns
1
9
28
848 ns
DUAL DATA POINTER
The timing of block moves of data memory is faster using the Dual Data Pointer (DPTR). The standard
8051 DPTR is a 16-bit value that is used to address off-chip data RAM or peripherals. In the
DS87C520/DS83C520, this data pointer is called DPTR0, located at SFR addresses 82h and 83h. These
are the original locations. Using DPTR requires no modification of standard code. The new DPTR at
SFR 84h and 85h is called DPTR1. The DPTR Select bit (DPS ) chooses the active pointer. Its location is
the lsb of the SFR location 86h. No other bits in register 86h have any effect and are 0. The user switches
between data pointers by toggling the lsb of register 86h. The increment (INC) instruction is the fastest
way to accomplish this. All DPTR-related instructions use the currently selected DPTR for any activity.
Therefore it takes only one instruction to switch from a source to a destination address. Using the Dual
Data Pointer saves code from needing to save source and destination addresses when doing a block move.
The software simply switches between DPTR0 and 1 once software loads them. The relevant register
locations are as follows:
DPL
82h
Low byte original DPTR
DPH
83h
High byte original DPTR
DPL1
84h
Low byte new DPTR
DPH1
85h
High byte new DPTR
DPS
86h
DPTR Select (lsb)
POWER MANAGEMENT
Along with the standard Idle and power down (Stop) modes of the standard 80C52, the
DS87C520/DS83C520 provides a new Power Management Mode. This mode allows the processor to
continue functioning, yet to save power compared with full operation. The DS87C520/DS83C520 also
features several enhancements to Stop mode that make it more useful.
POWER MANAGEMENT MODE (PMM)
Power Management Mode offers a complete scheme of reduced internal clock speeds that allow the CPU
to run software but to use substantially less power. During default operation, the DS87C520/DS83C520
uses four clocks per machine cycle. Thus the instruction cycle rate is Clock/4. At 33 MHz crystal speed,
the instruction cycle speed is 8.25 MHz (33/4). In PMM, the microcontroller continues to operate but uses
an internally divided version of the clock source. This creates a lower power state without external
components. It offers a choice of two reduced instruction cycle speeds (and two clock sources - discussed
below). The speeds are (Clock/64) and (Clock/1024).
相關PDF資料
PDF描述
DS87C520-QNL 8-BIT, OTPROM, 33 MHz, MICROCONTROLLER, PQCC44
DS87C520-QCL 8-BIT, OTPROM, 33 MHz, MICROCONTROLLER, PQCC44
DS87C520-ECL 8-BIT, OTPROM, 33 MHz, MICROCONTROLLER, PQFP44
DS87C520-MNL 8-BIT, OTPROM, 33 MHz, MICROCONTROLLER, PDIP40
DS87C520-ENL 8-BIT, OTPROM, 33 MHz, MICROCONTROLLER, PQFP44
相關代理商/技術參數(shù)
參數(shù)描述
DS87C520-MCL+ 功能描述:8位微控制器 -MCU EPROM/ROM High-Speed RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
DS87C520-MNL 功能描述:8位微控制器 -MCU EPROM/ROM High-Speed RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
DS87C520-MNL+ 功能描述:8位微控制器 -MCU EPROM/ROM High-Speed RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
DS87C520-QCL 功能描述:8位微控制器 -MCU EPROM/ROM High-Speed RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時鐘頻率:50 MHz 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風格:SMD/SMT
DS87C520-QCL/T&R 制造商:Maxim Integrated Products 功能描述:MICRO,OTP,HI SPD 44PLCC 33MHZ TRL - Tape and Reel 制造商:Maxim Integrated Products 功能描述:IC MCU EPROM/ROM 33MHZ HS 44PLCC