參數(shù)資料
型號(hào)： CT2579
廠商： Aeroflex Inc.
英文描述： APPLICATION NOTE #108
文件頁(yè)數(shù)： 12/41頁(yè)
文件大?。?/td> 112K
代理商： CT2579
12
APPLICATION NOTE #108
Released 9/98
5. Once the burst transfer has commenced it will complete, thus ensuring data consistency.
DMA TRANSFER TIMES
The DMA cycle transfers words from the FIFO to internal RAM at a rate of one word each 1
μSec. The maximum DMA cycle time could possibly occur for a 32 data word transfer if the
RAM is accessed at the beginning of NCMDSTRB Strobe. Maximum subsystem hold-off
time would be 8.5 μSec (NCMDSTRB Signal) + 32 μSec (0.5 μSec per word) for a total of
24.5 μSec.
TRANSMIT COMMAND
The incoming command word is verified for all protocol checks (such as parity and bit count).
The verified command word is placed on the T0-15 bus and the NVCR signal is strobed. It is
at this time that a message can be illegalized.
Any message can be illegalized by applying an active low on the NME signal within 600
nSec of the rising edge of NVCR at this time. The RT will respond with a Status word having
the Message Error bit set. See Section 1.2.1.1 for implementing the Message Illegalization.
The NCMDSTRB goes low indicating that a completely validated message has been
received. The validated Command Word again appears on the T0-15 bus at this time. The
end of the NCMDSTRB strobe will initiate the DMA cycle to transfer the data words from
internal RAM to the buffer FIFO.
Buffering the outgoing message with a FIFO means that the subsystem is allowed the most
flexibility to access the RAM without contending with 1553 bus traffic. In 1553, data words
are transmitted at a rate of 20 μSec per word or a maximum time of 640 μSec for a 32 word
transfer. Many other systems do not buffer the outgoing data at all. That means that the
RAM is periodically being accessed for data words from the RAM for up to 640 μSeconds.
The SmaRT unit buffers the outgoing data so that the RAM is completely available to the
subsystem after the DMA transfer from RAM occurs. The possibilities of memory contention
is greatly reduced and the contents of the outgoing data will not be affected by subsystem
operations.
The NCMDSTRB pulse is 8.5 μSec long and during this time interval, the bus arbitration
logic is active. If the subsystem has already begun a read/write operation before
NCMDSTRB, the NACK (acknowledge) signal will go low for 500 nSec allowing the
T0-15
NVCR
NME
CMD WD
500 nSec
600 nSec
Max
相關(guān)PDF資料
PDF描述
CT2581-02-IN-F84 CT2578 / CT2581 SIMPLE REMOTE TERMINAL FOR MIL-STD-1553 / 1760 & McAir
CT2581-02-IN-P119 CT2578 / CT2581 SIMPLE REMOTE TERMINAL FOR MIL-STD-1553 / 1760 & McAir
CT2581 CT2578 / CT2581 SIMPLE REMOTE TERMINAL FOR MIL-STD-1553 / 1760 & McAir
CT2581-02-XT-F84 CT2578 / CT2581 SIMPLE REMOTE TERMINAL FOR MIL-STD-1553 / 1760 & McAir
CT2578 CT2578 / CT2581 SIMPLE REMOTE TERMINAL FOR MIL-STD-1553 / 1760 & McAir
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
CT2580VY-SM 制造商:Panasonic Industrial Company 功能描述:MANUAL
CT2581 制造商:AEROFLEX 制造商全稱:AEROFLEX 功能描述:CT2578 / CT2581 SIMPLE REMOTE TERMINAL FOR MIL-STD-1553 / 1760 & McAir
CT2581-02-CG-F84 制造商:AEROFLEX 制造商全稱:AEROFLEX 功能描述:CT2578 / CT2581 SIMPLE REMOTE TERMINAL FOR MIL-STD-1553 / 1760 & McAir
CT2581-02-CG-P119 制造商:AEROFLEX 制造商全稱:AEROFLEX 功能描述:CT2578 / CT2581 SIMPLE REMOTE TERMINAL FOR MIL-STD-1553 / 1760 & McAir
CT2581-02-IN-F84 制造商:AEROFLEX 制造商全稱:AEROFLEX 功能描述:CT2578 / CT2581 SIMPLE REMOTE TERMINAL FOR MIL-STD-1553 / 1760 & McAir
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

*
*
*