外文翻譯微型計算機(jī)的數(shù)字音頻接口PROCESSORBASED數(shù)據(jù)記錄系統(tǒng)

1、微型計算機(jī)的數(shù)字音頻接口processor-based數(shù)據(jù)記錄系統(tǒng)thomas l. croxton, stanley j. stump, and william mcd. armstrongofphysiology生物部門、印第安納大學(xué)學(xué)校ofmedicine、印第安納波利斯,印地安那州的46223摘要：提出了一種廉價的接口實(shí)現(xiàn)了數(shù)字化數(shù)據(jù)直接轉(zhuǎn)移,從數(shù)字音頻處理器和視頻盒式錄音機(jī)的基礎(chǔ)數(shù)據(jù)采集系統(tǒng)設(shè)計和bezanilla(1985年。j .47:437 - 441)給一個ibm的pc / xt微型計算機(jī)。fortran語言的可收回軟件驅(qū)動接口很能干控制的錄音機(jī)和視頻數(shù)據(jù)采集后,立即開始承認(rèn)

2、的一個環(huán)節(jié)之前收集的數(shù)據(jù)。這使得分段分析數(shù)據(jù)的長的時間間隔,否則將超過記憶能力的微型計算機(jī)。高容量的數(shù)據(jù)記錄系統(tǒng)所設(shè)計的f。bezanilla(1985)是很有價值的從業(yè)人員記錄單通道,因?yàn)樗梢源鎯槎ǖ赖姆浅＞_的數(shù)據(jù)(16位分辨率)、采樣在一個流暢的速度增長(44100個樣本/秒)、延長一段時間(3 h).我們有,不過,遇到限制電腦技術(shù)問題進(jìn)行了分析這樣的數(shù)據(jù)記錄。尤其是當(dāng)數(shù)據(jù)播放時是很難精確或可以嗎選擇一個數(shù)值的數(shù)據(jù)存儲在計算機(jī)記憶。這個困難促使我們開發(fā)一個接口bezanilla之間的數(shù)據(jù)記錄系統(tǒng)和pc / xt微型計算機(jī)模型(ibm儀器有限公司,ibm公司,danbury,ct)。

3、文中介紹了界面能夠獲取的數(shù)據(jù)重復(fù)同樣的間隔內(nèi)嗎和檢索連續(xù)間隔。后者能力允許單通道記錄分析有很大的影響在持續(xù)時間超過的數(shù)據(jù)存儲容量的電腦(< 6 s數(shù)據(jù)每512 k,寬帶下載1秒鐘的記憶)。我們由一個開關(guān)盒接口選擇左邊或者右通道采樣、一個插件電腦板那multiplexes 16位數(shù)據(jù)轉(zhuǎn)移的8位元計算機(jī)數(shù)據(jù)總線,和一個匯編語言程序控制視頻錄音機(jī)(vcr)和指導(dǎo)在時序存放數(shù)據(jù)的內(nèi)存位置。兩功能模式是可得到的。在這個互動的模式錄像機(jī)和數(shù)據(jù)數(shù)組開始重復(fù),直到充滿了一個鍵被按下。錄像,然后當(dāng)場-20年代的位置開始之前收集到的數(shù)據(jù)。在自動模式調(diào)用程序提供了一個標(biāo)記42歲的順序,以前采樣數(shù)據(jù)點(diǎn)。vcr開

4、始時,輸入的數(shù)據(jù)進(jìn)行了比較,結(jié)果表明該標(biāo)記物的一部分。如果找到匹配的陣列的數(shù)據(jù)都被填滿立即與數(shù)據(jù)跟蹤標(biāo)記。充滿立即與數(shù)據(jù)跟蹤標(biāo)記。這然后當(dāng)場錄像-20年后,一個位置開始的數(shù)據(jù)和控制返回到調(diào)用程序。如果沒有找到匹配的在一個可調(diào)的時期回放的(1分鐘0.5 h),錄影帶是當(dāng)場60年代和子程序返回一個國旗表示這些數(shù)據(jù)收集并不成功。如果最后的42數(shù)據(jù)每一個記錄點(diǎn)作為標(biāo)記為下一個記錄,序貫子功能調(diào)用在自動模式將產(chǎn)量檢索的連續(xù)數(shù)據(jù)塊。雖然我們是硬件接口描述特定對我們的儀器和計算機(jī),適應(yīng)設(shè)備應(yīng)直截了當(dāng)。然而,速度8255接口芯片的限制,以防止出現(xiàn)利用這個特別的接口at-type ibm電腦那操作的6 - 8兆

5、赫的鐘速度。我們接口硬件中所示圖1?？偝杀倦娔X板和其它部件150美元。這所設(shè)計的數(shù)字輸出階段bezanilla提供的話時鐘左眼和右眼的數(shù)據(jù)通道和16個平行數(shù)據(jù)線路。在我們的數(shù)字音頻處理器(階級501;unitrade公司、費(fèi)城、pa)這些信號是可得到的在一個25-pin連接器在后方的底盤。一個帶狀電纜分機(jī)號是用來連接這些線條類似的接頭安裝在一邊,5”×2.5 " x 1.5”塑料盒。點(diǎn)對點(diǎn)的線路連接在盒子里一個37-pin數(shù)據(jù)線路接頭安裝在對面盒,連接到一個時鐘線渠道的選擇開關(guān)、控制線路和線路從37-pin錄像機(jī)連接器連接到一個六角五接頭。第二個帶狀電纜連接37-pin延伸

6、連接件的開關(guān)盒的匹配連接器插件電腦板。圖1的電子線路數(shù)字接口。并行數(shù)字輸出的數(shù)字音頻處理器被a和b的港口8255可編程外圍接口芯片p1012計算機(jī)板上。8255年設(shè)定每一個16位數(shù)據(jù)轉(zhuǎn)換成詞兩個8字在電腦上轉(zhuǎn)移公共汽車。電線連接器,db-25之間dc-37連接器在開關(guān)盒便利數(shù)字音頻處理器連接到p1012計算機(jī)卡。選擇數(shù)字音頻處理器數(shù)據(jù)信道是由開關(guān)選擇時鐘信號的輸入連接到8255端口的握手c成分添加到pi012卡激活玩,重新再來,讓停止功能的視頻錄音機(jī)的控制下,通過optoisolators 6和7位港口c。metrabyte公司、taunton,馬02780)修改允許由電腦控制錄放影機(jī)。該板包

7、含一位8255可編程外圍接口芯片(英特爾公司、圣克拉拉、ca),一個數(shù)據(jù)總線緩沖區(qū),和一個地址譯碼器。未使用的區(qū)域在頂部的電路板提供充足的房間一根電線包裹集成電路哪幢房子的其它部件的插座中顯示圖1 .從添加組件連接現(xiàn)有板可以改變,以適應(yīng)焊接到短距離跳投電路一側(cè)的板。唯一的其他修改需要的是去除的電源電壓從針12、14、16和18 37-pin連接的,所以這些線可以用于錄像機(jī)控制。5 v - 12 v,和+ 12 v線路,最好是不需要被中斷割下了3電路板靠近他們接觸痕跡計算機(jī)總線。切除+ 5 v遠(yuǎn)銷18的要求兩個邊路的切割痕跡頂部和方法37-pin底部連接組件的一面板和安裝一個跳投,把比分重新這些

8、兩個+ 5 v痕跡。這運(yùn)行,停止,后退、我們的錄像機(jī)功能(模型sl-hf450;索尼公司,美國長島的城市,紐約通常是由沮喪spst觸發(fā)開關(guān)位于前面板。修改這個錄像機(jī)僅含安裝了一個六角五連接器。背面板及連接桿地面和。沒有根植,雙方的運(yùn)行,停止,后退、開關(guān)。這些線是相連的,通過開關(guān)盒,到三個人4 n36 optoisolators安裝在p1012電路板。激活的optoisolators相當(dāng)于沉悶相應(yīng)的開關(guān),錄放影機(jī)。宏匯編源代碼圖2為控制界面。這個子程序可以對計劃8255年為數(shù)據(jù)傳輸、存儲數(shù)據(jù)微電腦記憶,和控制視頻盒式錄音機(jī)。致電本程序指令,描述了它的算法給出了評論。軟件驅(qū)動數(shù)據(jù)傳輸正在寫的宏匯編

9、,是微軟打算聯(lián)系微軟fortran調(diào)用程序。一個簡要介紹了算法也緊隨其后。細(xì)節(jié)算法和指令致電本程序在備注中提供的源代碼列在圖2。8255年是程序?yàn)檩斎?接二連三的港口b .在這個配置中,0 - 5位用于港口c握手。單詞是搭成的數(shù)據(jù)端口a和b時鐘信號通過直接選擇比特2和4港口0 c點(diǎn)微機(jī)樣品港口c(intr b)當(dāng)數(shù)據(jù)來確定詞被抓住了。這然后輸入一個字,微機(jī)登記儲存在記憶中。記憶是寄款8每一個點(diǎn)(16個字節(jié))。每一個段落之間的部分增加和偏移登記注冊減少16歲。當(dāng)所需資料收集停止數(shù)量的段落的數(shù)據(jù)已經(jīng)存儲。檢測鍵盤條目是經(jīng)由函數(shù)調(diào)用磁盤的時間操作系統(tǒng)(dos操作系統(tǒng))。在自動模式下,提供一個程序標(biāo)記

10、組成的采樣點(diǎn)42之前。一個32位的模板是由第一個最低有效位32分的標(biāo)記。最重要的每一個采樣點(diǎn)的觀點(diǎn)是旋轉(zhuǎn)成一個32位的一對寄存器和對比模板。這在比較了兩個階段。僅當(dāng)?shù)谝粋€16位比賽,其他的16位比較。因?yàn)?因?yàn)檎鎸?shí)的數(shù)據(jù),最低有效位基本上是隨機(jī)的,一個16位比賽時發(fā)生的頻率大約在216年一次每1.5秒。如果一個特定數(shù)目的一半比賽發(fā)生在總找到匹配的子程序中流產(chǎn)返回一個錯誤代碼。如果一個總找到匹配的數(shù)據(jù)收藏是開始。前兩個點(diǎn)(對應(yīng)這33rd和34th分漏掉標(biāo)記)。這未來的8點(diǎn)是:以一個數(shù)組的形式存儲在馬上preceeds陣列的數(shù)據(jù)在內(nèi)存中。我們建議調(diào)用程序確認(rèn)這些8點(diǎn)都是相同的到最后的8分42-po

11、int標(biāo)記。 此后,點(diǎn)中存儲的數(shù)據(jù)的數(shù)組。完成的控制,通過使用錄像機(jī)的位元第六條、第七條的規(guī)定的港口c 8255。這些都是沒有要求握手,編程為輸出。7442bcd-to-decimal轉(zhuǎn)換器是用來demultiplex這些兩位。代碼c6 c7 = 00,03,和10個激活玩,停止,收、功能,分別。位c6、c7通常設(shè)定,導(dǎo)致任何行動。當(dāng)一方或兩位被復(fù)位,適當(dāng)?shù)妮敵龅?442驅(qū)使低,激活相應(yīng)的4 n36 optoisolator。一個軟件定時器是用來控制的時間optoisolator激活與時間之間錄像機(jī)的命令。我們也觀察到的唯一缺陷測試接口調(diào)用子程序偶爾的失敗來偵測標(biāo)記。這發(fā)生< 1%的時間

12、。通常,一個第二給同一標(biāo)記子程序執(zhí)行正確的。我們相信這次失敗源于誤讀錄像。作者將很高興提供感興趣的讀者與磁盤拷貝的列在圖二子程序和它的組裝目標(biāo)代碼。有這樣要的的朋友在郵寄是請在郵件里放上格式化好的軟盤。參考:bezanilla,f . 1985。 一個高容量的數(shù)據(jù)記錄設(shè)備的基于數(shù)字音頻處理器和一個視頻盒式錄音機(jī)。雜志。j。47:437 - 441。a microcomputer interface for a digital audio processor-based data recording systemthomas l. croxton, stanley j. stump, and w

13、illiam mcd. armstrongdepartment ofphysiology and biophysics, indiana university school ofmedicine, indianapolis,indiana 46223abstract an inexpensive interface is described that performs direct transfer of digitized data from the digital audioprocessor and video cassette recorder based data acquisiti

14、on system designed by bezanilla (1985, biophys. j.,47:437-441) to an ibm pc/xt microcomputer. the fortran callable software that drives this interface is capableof controlling the video cassette recorder and starting data collection immediately after recognition of a segment ofpreviously collected d

15、ata. this permits piecewise analysis of long intervals of data that would otherwise exceed thememory capability of themicrocomputer.the high capacity data recording system designed by f.bezanilla (1985) is of great value to practitioners ofsingle-channel recording since it allows storage of two chan

16、nels of very precise data (16 bit resolution), sampled at an acceptably fast rate (44,100 samples/s), for extended periods of time (up to 3 h). we have, however, encountered technical problems which limit the computerized analysis of data recorded in this way. in particular, when the data are played

17、 back it is difficult to accurately or reproducibly select a given interval of data for storage in computer memory. this difficulty prompted us to develop an interface between bezanilla's data recording system and the model pc/xt microcomputer (ibm instruments inc., ibm corp., danbury, ct). the

18、interface described herein is capable of retrieving the same interval of data repeatedly and of retrieving contiguous intervals. the latter capability allows analysis of single channel records which greatly exceed in duration the data storage capacity of the computer(<6 s data per 512 kbytes memo

19、ry).our interface consists of a switch box that selects the left or right channel for sampling, a plug-in computer board that multiplexes the 16-bit data for transfer on the 8-bit computer data bus, and an assembly language subroutine that controls the video cassette recorder (vcr) and directs stora

20、ge of data in sequential memory locations. two functional modes are available. in the interactive mode the vcr is started and the data array is filled repetitively until a key is pressed. the video tape is then rewound to a position -20 s before the beginning of the collected data. in the automatic

21、mode the calling program provides a marker of 42 sequential, previously sampled data points. the vcr is started and incoming data are compared with a portion of this marker. if a match is found the data array is filled with the data that immediately follow the marker. the video tape is then rewound

22、to a position -20 s before the beginning of the data and control returns to the calling program. if no match is found within an adjustable period of playback (-1 min to 0.5 h), the video tape is rewound-60 s and the subroutine returns a flag which indicates that data collection was not successful. i

23、f the last 42 data points of each record are used as the marker for the next record, sequential subroutine calls in the automatic mode will yield retrieval of contiguous blocks of data.although the interface we describe is hardware specific to our instruments and computer, adaptation to other equipm

24、ent should be straightforward. however, speed limitations of the 8255 interface chip appear to preclude use of this particular interface with ibm at-type computers that operate at a 6-8 mhz clock speed. our interface hardware is depicted in fig. 1. total cost for the computer board and additional co

25、mponents is -$150. the digital output stage designed by bezanilla provides word clocks for the right and left data channels and 16 parallel data lines. in our digital audio processor (dass 501; unitrade inc., philadelphia, pa) these signals are available on a 25-pin connector at the rear of the chas

26、sis. a ribbon cable extension is used to connect these lines to a similar connector mounted on one side of a 5" x 2.5" x 1.5" plastic box. point-to-point wiring within the box connects the data lines to a 37-pin connector mounted on the opposite side of the box, connects the clock lin

27、es to a channel selector switch, and routes control lines for the vcr from the 37-pin connector to a 5-pin hex connector. a second ribbon cable extension connects the 37-pin connector of the switch box to the matching connector of a plug-in computer board.figure 1 electronic circuitry of digital int

28、erface. the parallel digital output of the digital audio processor is routed to ports a and b of an 8255 programmable peripheral interface chip on a p1012 computer board. the 8255 is programmed to convert each 16-bit data word to two 8-bit words for transfer on the computer bus. wiring between a db-

29、25 connector and a dc-37 connector in the switch box facilitates connection of the digital audio processor to the p1012 computer card. choice of digital audio processor data channel is made by switch selection of the clock signal to be connected to handshaking inputs of the 8255 port c. components a

30、dded to the pi012 card activate the play, rewind, and stop functions of the video cassette recorder via optoisolators under the control of bits 6 and 7 of port c.the computer board we now employ (model pio12,metrabyte corp., taunton, ma 02780) was modified to allow computerized control of the vcr. t

31、his board contains an 8255 programmable peripheral interface chip (intel corp., santa clara, ca), a data bus buffer, and an address decoder. an unused area at the top of the circuit board provides ample room for wire wrap integrated circuit sockets which house the additional components shown in fig.

32、 1. connections from the added components to the existing board may be made with short jumpers soldered to the circuit side of the board. the only other modification required is the removal of power supply voltages from pins 12, 14, 16, and 18 of the 37-pin connector so that these lines may be used

33、for vcr control. the -5 v, - 12 v, and + 12 v lines are not required and are best interrupted by cutting three circuit board traces near their contacts with the computer bus. removal of + 5 v from pin 18 requires cutting of two wide traces which approach the top and bottom of the 37-pin connector on

34、 the component side of the board and installation of a jumper to reconnect these two + 5 v traces. the play, stop, and rewind functions of our vcr (model sl-hf450; sony corp. of america, long island city,ny) are normally triggered by depressing spst switches located on the front panel. modification

35、of this vcr consists simply of mounting a 5-pin hex connector to the back panel and connecting pins to ground and to the ungrounded sides of the play, stop, and rewind switches. these lines are connected, via the switch box, to three 4n36 optoisolators mounted on the p1012 circuit board. activating

36、one of the optoisolators is equivalent to depressing the corresponding switch of the vcr.the software that drives the data transfer is written for the microsoft macro assembler and is intended to be linked with a microsoft fortran calling program. a brief overview of the algorithm follows. details o

37、f the algorithm and instructions for calling the subroutine are provided in the remarks of the source code listed in fig. 2. the 8255 is programmed for strobed input of ports a and b. in this configuration, bits 0-5 of port c are used for handshaking. the data word is latched into ports a and b by d

38、irecting the selected clock signal to bits 2 and 4 of port c. the microcomputer samples bit 0 of port c (intr b) to determine when the data word has been latched. the word is then input to a microcomputer register and is stored in memory. memory is addressed in paragraphs of 8 points (16 bytes) each

39、. between each paragraph the segment register is incremented and the offset register is reduced by 16. data collection ceases when the required number of paragraphs of data has been stored. detection of keyboard entry is made via function calls to the disk operating system (microsoft dos).figure 2 m

40、acro assembler source code for control of interface. this subroutine programs the 8255 for data transfer, stores data in microcomputer memory, and controls the video cassette recorder. instructions for calling the subroutine and a description of its algorithm are given in the comments.in the automat

41、ic mode the program is provided with a marker consisting of 42 previously sampled points. a 32-bit template is constructed from the least significantbits of the first 32 points of the marker. the least significant bit of each sampled point is rotated into a 32-bit pair of registers and is compared w

42、ith the template. this comparison is done in two stages. only if the first 16 bits match, are the other 16 bits compared. since, for real data, the least significant bits are essentially random, a 16-bit match occurs with a frequency of 1 in 216 or about once every 1.5 s. if a specified number of ha

43、lf matches occur before a total match is found the subroutine aborts and returns an error code. if a total match is found data collection is started. the first two points (corresponding to the 33rd and 34th points of the marker) are missed. the next eight points are stored in an array that immediately preceeds the data array in memory. we recommend that the calling program verify that these 8 points are identical to the last 8 points of the 42-point