參數(shù)資料
型號(hào): ST92186B3BK
廠商: STMICROELECTRONICS
元件分類: 微控制器/微處理器
英文描述: 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PDIP32
封裝: PLASTIC, SDIP-32
文件頁數(shù): 78/148頁
文件大?。?/td> 1664K
代理商: ST92186B3BK
Obsolete
Product(s)
- Obsolete
Product(s)
Obsolete
Product(s)
- Obsolete
Product(s)
35/148
ST92186B - DEVICE ARCHITECTURE
2.6 ADDRESS SPACE EXTENSION
To manage 4 Mbytes of addressing space it is
necessary to have 22 address bits. The MMU
adds 6 bits to the usual 16-bit address, thus trans-
lating a 16-bit virtual address into a 22-bit physical
address. There are 2 different ways to do this de-
pending on the memory involved and on the oper-
ation being performed.
2.6.1 Addressing 16-Kbyte Pages
This extension mode is implicitly used to address
Data memory space.
The Data memory space is divided into 4 pages of
16 Kbytes. Each one of the four 8-bit registers
(DPR[3:0], Data Page Registers) selects a differ-
ent 16-Kbyte page. The DPR registers allow ac-
cess to the entire memory space which contains
256 pages of 16 Kbytes.
Data paging is performed by extending the 14 LSB
of the 16-bit address with the contents of a DPR
register. The two MSBs of the 16-bit address are
interpreted as the identification number of the DPR
register to be used. Therefore, the DPR registers
are involved in the following virtual address rang-
es:
DPR0: from 0000h to 3FFFh;
DPR1: from 4000h to 7FFFh;
DPR2: from 8000h to BFFFh;
DPR3: from C000h to FFFFh.
The contents of the selected DPR register specify
one of the 256 possible data memory pages. This
8-bit data page number, in addition to the remain-
ing 14-bit page offset address forms the physical
22-bit address (see Figure 15).
A DPR register cannot be modified via an address-
ing mode that uses the same DPR register. For in-
stance, the instruction “POPW DPR0” is legal only
if the stack is kept either in the register file or in a
memory location above 8000h, where DPR2 and
DPR3 are used. Otherwise, since DPR0 and
DPR1 are modified by the instruction, unpredicta-
ble behaviour could result.
Figure 15. Addressing via DPR[3:0]
DPR0
DPR1
DPR2
DPR3
00
01
10
11
16-bit virtual address
22-bit physical address
8 bits
MMU registers
2
MS
B
14 LSB
相關(guān)PDF資料
PDF描述
ST92195B2T1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PQFP64
ST92195B3B1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PDIP56
ST92195B4B1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PDIP56
ST92195B5T1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PQFP64
ST92195B6T1/XXX 16-BIT, MROM, 24 MHz, MICROCONTROLLER, PQFP64
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
ST92195 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER
ST92195B 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER
ST92195B1 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER
ST92195B1B1 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER
ST92195B1T1 制造商:STMICROELECTRONICS 制造商全稱:STMicroelectronics 功能描述:32-64K ROM HCMOS MCU WITH ON-SCREEN-DISPLAY AND TELETEXT DATA SLICER