參數(shù)資料
型號: MC68HC11KW1
廠商: MOTOROLA INC
元件分類: 微控制器/微處理器
英文描述: High-density complementary metal oxide semiconductor HCMOS) microcontroller unit
中文描述: 8-BIT, EEPROM, 4 MHz, MICROCONTROLLER, PQFP100
封裝: TQFP-100
文件頁數(shù): 67/238頁
文件大?。?/td> 798K
代理商: MC68HC11KW1
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁第37頁第38頁第39頁第40頁第41頁第42頁第43頁第44頁第45頁第46頁第47頁第48頁第49頁第50頁第51頁第52頁第53頁第54頁第55頁第56頁第57頁第58頁第59頁第60頁第61頁第62頁第63頁第64頁第65頁第66頁當(dāng)前第67頁第68頁第69頁第70頁第71頁第72頁第73頁第74頁第75頁第76頁第77頁第78頁第79頁第80頁第81頁第82頁第83頁第84頁第85頁第86頁第87頁第88頁第89頁第90頁第91頁第92頁第93頁第94頁第95頁第96頁第97頁第98頁第99頁第100頁第101頁第102頁第103頁第104頁第105頁第106頁第107頁第108頁第109頁第110頁第111頁第112頁第113頁第114頁第115頁第116頁第117頁第118頁第119頁第120頁第121頁第122頁第123頁第124頁第125頁第126頁第127頁第128頁第129頁第130頁第131頁第132頁第133頁第134頁第135頁第136頁第137頁第138頁第139頁第140頁第141頁第142頁第143頁第144頁第145頁第146頁第147頁第148頁第149頁第150頁第151頁第152頁第153頁第154頁第155頁第156頁第157頁第158頁第159頁第160頁第161頁第162頁第163頁第164頁第165頁第166頁第167頁第168頁第169頁第170頁第171頁第172頁第173頁第174頁第175頁第176頁第177頁第178頁第179頁第180頁第181頁第182頁第183頁第184頁第185頁第186頁第187頁第188頁第189頁第190頁第191頁第192頁第193頁第194頁第195頁第196頁第197頁第198頁第199頁第200頁第201頁第202頁第203頁第204頁第205頁第206頁第207頁第208頁第209頁第210頁第211頁第212頁第213頁第214頁第215頁第216頁第217頁第218頁第219頁第220頁第221頁第222頁第223頁第224頁第225頁第226頁第227頁第228頁第229頁第230頁第231頁第232頁第233頁第234頁第235頁第236頁第237頁第238頁
MC68HC11KW1
MOTOROLA
4-23
OPERATING MODES AND ON-CHIP MEMORY
4
4.4.2
Extended addressing
Memory expansion is achieved by manipulating the CPU address lines such that, even though the
CPU cannot distinguish more than 64K bytes of physical memory, up to 1M byte can be accessed
through a paged memory scheme. Additional address lines XA[18:13] are provided as alternative
functions of port G pins. Bits in the port G assignment register (PGAR) define which port G pins are to
be used for memory expansion address lines and which are to be used for general-purpose I/O.
In order to access expanded memory, the user must first allocate a range of the 64K byte address
space to be used for the window(s) through which external, expanded memory is viewed by the
CPU. The size and placement of the window(s) depend on values written to the MMSIZ and
MMWBR registers, respectively. Which bank or page of the expanded memory that is present in
the window(s) at a given time is dependent on values written to the MM1CR and MM2CR
registers.
Up to two windows can be designated and each can be programmed to 0K (disabled), 8K, 16K,
or 32K bytes. The base address for each window must be an integer multiple of the window size,
with the exception of the 32K byte window, for which the base address can be at $0000, $4000,
or $8000.
If the windows are defined in such a way that they overlap, bank window 1 has priority and the part
of window 2 that is not overlapped by bank window 1 remains active. If a window is defined such
that it overlaps any internal registers, RAM, or EEPROM, then the portion of the registers, RAM,
or EEPROM that is overlapped is repeated in all banks associated with that window.
Coming out of reset, the reset vector is fetched from external memory. Since the memory
expansion lines are disabled coming out of reset and can be internally pulled to logic level one,
any external system that uses these expansion address lines sees them as all ones. In this case,
the reset vector is fetched from $7FFFE–$7FFFF. Systems using external but not
expanded
memory still fetch the reset vector from $FFFE–$FFFF. This is the reset vector's normal position
at the top of the M68HC11 CPU's conventional 64K byte address space.
Expanded memory is addressed by using a combination of the CPU's normal address lines
ADDR[15:0] and the expansion address lines XA[18:13]. Window size and the number of banks
associated with the window determine exactly which address lines are used. The additional
address lines (XA[18:13]) determine which bank is present in a window at a given time. The lower
three expansion address lines (XA[15:13]) are used only when needed by the CPU and replace
the CPU's equivalent address lines (ADDR[15:13]). Table 4-9 shows which address lines are used
for various configurations of expanded memory.
A special case exists when the bank size is 32K bytes and the window base address is $4000.
Normally, when the bank size is 32K bytes and the bank address is $0000 or $8000, CPU address
lines ADDR[14:0] select individual bytes within the 32K byte space and the ADDR[14:0] pins are
connected to address lines (A[14:0]) of the memory device. When the base address is $4000, the CPU
address signal ADDR14 must be inverted to allow 32K bytes of contiguous memory. The
MC68HC11KW1 CPU drives the inverted CPU ADDR14 signal onto the XA14 pin when the window
is active. In this case, the XA14 signal must be connected to the address line 14 of the memory device.
When the window is not active, the XA14 pin is driven with the non-inverted CPU ADDR14 signal.
TPG
65
相關(guān)PDF資料
PDF描述
MC68HC11L6CFN HCMOS MICROCONTROLLER UNIT
MC68HC11L6FS HCMOS MICROCONTROLLER UNIT
MC68HC11L6FU HCMOS MICROCONTROLLER UNIT
MC68HC11L6L HCMOS MICROCONTROLLER UNIT
MC68HC11L6MFB HCMOS MICROCONTROLLER UNIT
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MC68HC11L0 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:CONFIG Register Programming for EEPROM-based M68HC11 Microcontrollers
MC68HC11L0CFN2 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS MICROCONTROLLER UNIT
MC68HC11L0CFN3 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS MICROCONTROLLER UNIT
MC68HC11L0CFU2 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS MICROCONTROLLER UNIT
MC68HC11L0CFU3 制造商:FREESCALE 制造商全稱:Freescale Semiconductor, Inc 功能描述:HCMOS MICROCONTROLLER UNIT