參數(shù)資料
型號(hào)： NSAM266SVLJ
廠商： National Semiconductor Corporation
元件分類(lèi)： FLASH
英文描述： 4 Mbit Uniform Sector, Serial Flash Memory
中文描述： 4兆位統(tǒng)一部門(mén)，串行閃存
文件頁(yè)數(shù)： 31/52頁(yè)
文件大小： 571K
代理商： NSAM266SVLJ
2.0 Software
(Continued)
4. When a return value is transmitted, the MWRDY signal is
deactivated after every byte, and activated again when
the CompactSPEECH is ready to send another byte, or to
receive a new command.
The MWRDY signal is activated (cleared to 0) after reset,
and after a protocol time-out. (See Section 2.12.2.)
The MWRQST signal is used as follows:
1. The MWRQST signal is activated (cleared to 0), when the
status word is changed.
2. The MWRQST signal remains active (0), until the
CompactSPEECH receives a GSW command.
Figure 2-5 illustrates the sequence of activities during a
MICROWIRE data transfer.
2.12.2 Interface Protocol Error Handling
Interface Protocol Time-Outs
Depending on the CompactSPEECH’s state, if more than
20 ms–30 ms elapse between two consecutive byte trans-
missions, or two byte receptions, within the same command
or return value, after the MWRDY signal is asserted, a time-
out event occurs, and the CompactSPEECH responds as
follows:
1. Sets the error bit in the status word to 1.
2. Sets the EVDTIMEOUT bit in the error word to 1.
3. Activates the MWRQST signal (clears it to 0).
4. Activates the MWRDY signal (clears it to 0).
5. Waits for a new command. (After a time-out occurs, the
microcontroller must wait at least four milliseconds before
issuing the next command.)
Echo Mechanism
The CompactSPEECH echoes back to the microcontroller
all the bits received by the CompactSPEECH. Upon detec-
tion of an error in the echo, the microcontroller should stop
the protocol clock, which eventually causes a time-out error
(i.e., ERRDTIMEOUT bit is set in the error word).
Note:
When a command has a return value, the CompactSPEECH transmits
bytes of the return value instead of the echo value.
The CompactSPEECH transmits a byte as an echo when it
receives the value 0xAA from the microprocessor. Upon de-
tection of an error the CompactSPEECH activates the
MWRQST signal, and sets the ERRDCOMM bit in the error
word.
2.13 THE MASTER MICROWIRE INTERFACE
The CompactSPEECH’s Master MICROWIRE controller im-
plements the MICROWIRE/PLUS interface in master mode.
It enables the CompactSPEECH to control flash devices.
Several devices may share the Master MICROWIRE chan-
nel. This can be implemented by connecting device selec-
tion signals to general purpose output ports.
2.13.1 Master MICROWIRE Data Transfer
The Signals
The Master MICROWIRE controller’s signals are the Master
MICROWIRE serial CLocK (MMCLK), the Master MICRO-
WIRE serial Data OUT (MMDOUT) signal and the Master
MICROWIRE serial Data In (MMDIN) signal.
The Master MICROWIRE controller can handle up to four
flash devices. The CompactSPEECH uses the signals,
CS0–CS3, as required for the number of devices in use, as
device chip-select signals.
The Clock for Master MICROWIRE Data Transfer
Before data can be transferred, the transfer rate must be
determined and set. The rate of data transfer on the Master
MICROWIRE is determined by the Master MICROWIRE se-
rial CLocK (MMCLK) signal. This rate is the same as the
Codec CLocK (CCLK) signal. As long as the Master MICRO-
WIRE is transferring data, the codec interface must be en-
abled and its sampling rate should not be changed.
TL/EE/12584–29
FIGURE 2-5. Sequence of Activities during a MICROWIRE Byte Transfer
http://www.national.com
31
相關(guān)PDF資料
PDF描述
NSAM266SA 4 Mbit Uniform Sector, Serial Flash Memory
NSAM266SAA 4 Mbit Uniform Sector, Serial Flash Memory
NSB8 BASIC interpreter for Z80 family
NSB9435T1 High Current Bias Resistor Transistors(高強(qiáng)度電流偏置電阻晶體管)
NSBA114EDXV6T1 Dual Bias Resistor Transistors(雙偏置電阻晶體管)
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
NSAM2AS1012VDC 制造商:DBLECTRO 制造商全稱(chēng):DB Lectro Inc 功能描述:Suitable for automobile accessories
NSAM2AS1018VDC 制造商:DBLECTRO 制造商全稱(chēng):DB Lectro Inc 功能描述:Suitable for automobile accessories
NSAM2AS1024VDC 制造商:DBLECTRO 制造商全稱(chēng):DB Lectro Inc 功能描述:Suitable for automobile accessories
NSAM2AS103VDC 制造商:DBLECTRO 制造商全稱(chēng):DB Lectro Inc 功能描述:Switching capacity up to 20A
NSAM2AS105VDC 制造商:DBLECTRO 制造商全稱(chēng):DB Lectro Inc 功能描述:Suitable for automobile accessories
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫(xiě)一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*