參數(shù)資料
型號: MD80C52CXXX-16SCD
廠商: TEMIC SEMICONDUCTORS
元件分類: 微控制器/微處理器
英文描述: 8-BIT, MROM, 16 MHz, MICROCONTROLLER, CDIP40
文件頁數(shù): 64/80頁
文件大?。?/td> 5152K
代理商: MD80C52CXXX-16SCD
264
XMEGA A [MANUAL]
8077I–AVR–11/2012
Figure 24-1. Base Address
24.3.2 Address Size
The address size selects how many bits of the address should be compared when generating a chip select. The address
size can be anywhere from 256 bytes to 16MB. If the address space is set to anything larger than 4KB, the base address
must be on a boundary equal to the address space. For example, with 1MB address space for a chip select, the base
address must be on a 1MB, 2MB, etc. boundary.
If the EBI is configured so that the address spaces overlap, the internal memory space will have priority, followed by chip
select 0 (CS0), CS1, CS2, and CS3.
24.3.3 Chip Select as Address Lines
If any chip select lines are unused, these can, in some combinations, be used as address lines. This enables larger
external memory or external CS generation. Each column in Figure 24-2 on page 264 shows enabled chip select lines
(CSn) and the address lines available on unused chip select lines (An). The right-hand column shows that all four CS
lines are used as address lines when only CS3 is enabled.
Figure 24-2. Chip Select and address line combinations
24.4
EBI Clock
The EBI is clocked from the Peripheral 2x (ClkPER2) Clock. This clock can run at the CPU Clock frequency, or at two times
the CPU Clock frequency. This can be used to lower the EBI access time. Refer to “System Clock and Clock Options” on
page 79 for details the Peripheral 2x Clock and how to configure this.
24.5
SRAM Configuration
When used with SRAM, the EBI can be configured with no multiplexing, or it can employ various address multiplexing
modes by using external address latches. When a limited number of pins are available on the device for the EBI, address
latch enable (ALE) signals are used to control the external latches that multiplex address lines from the EBI. The
ADDRESS[23:n]
BASEADDR[23:n]
=
ADDRESS[n-1:0]
A[n-1:0]
D[7:0]
CS
CS3
CS2
CS1
CS0
CS3
CS2
CS1
A16
CS3
CS2
A17
A16
A19
A18
A17
A16
相關(guān)PDF資料
PDF描述
MF180C51-16R 8-BIT, MROM, 16 MHz, MICROCONTROLLER, PQFP44
MQ80C32E-20SHXXX:D 8-BIT, 20 MHz, MICROCONTROLLER, CQFP44
MQ80C32E-36/883D 8-BIT, 36 MHz, MICROCONTROLLER, CQFP44
MC80C52TXXX-16SBD 8-BIT, MROM, 16 MHz, MICROCONTROLLER, CDIP40
MR80C32-25SBR 8-BIT, 25 MHz, MICROCONTROLLER, CQCC44
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MD80C86 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:CMOS 16-Bit Microprocessor
MD80C862 制造商:Intel 功能描述:PROCESSOR:MICRO-PROCESSOR
MD80C86-2 制造商:INTERSIL 制造商全稱:Intersil Corporation 功能描述:CMOS 16-Bit Microprocessor
MD80C86-2/883 制造商:Intersil Corporation 功能描述:MPU 16BIT CMOS 8MHZ 40CDIP - Rail/Tube 制造商:Rochester Electronics LLC 功能描述:CPU 16BILT 5V CMOS 8MHZ 40CDIP - Bulk
MD80C86-2/B 制造商:Intersil Corporation 功能描述:MPU 16BIT CMOS 8MHZ 40CDIP - Rail/Tube