SHORT
8700
BGA/2021+
原裝現(xiàn)貨
SHORT
2000
BGA/2024+
原廠原裝現(xiàn)貨庫存支持當(dāng)天發(fā)貨
SHORT
48000
BGA/24+
原裝現(xiàn)貨,可開專票,提供賬期服務(wù)
SHORT
5000
BGA/23+
優(yōu)勢(shì)產(chǎn)品大量庫存原裝現(xiàn)貨
SHORT
3000
BGA/N/A
原裝正品熱賣,價(jià)格優(yōu)勢(shì)
SHORT
41364
BGA/25+
原裝認(rèn)證有意請(qǐng)來電或QQ洽談
SHORT
15800
BGA/24+
旋爾只做進(jìn)口原裝,假一賠十...
SHORT
4
-/14+
原裝現(xiàn)貨熱賣
SHORT
521010
NR/2017+
-
SHORT
6608
BGA/2024+
現(xiàn)貨假一罰萬只做原裝現(xiàn)貨
SHORT
63422
BGA/2215+
原裝現(xiàn)貨,可提供一站式配套服務(wù)
SHORT
65286
-/21+
全新原裝現(xiàn)貨,長期供應(yīng),免費(fèi)送樣
SHORT
8391
BGA/22+
特價(jià)現(xiàn)貨,提供BOM配單服務(wù)
SHORT
521010
NR/2017+
-
SHORT
5000
BGA/24+
優(yōu)勢(shì)渠道現(xiàn)貨,提供一站式配單服務(wù)
SHORT
60701
BGA/24+
深圳原裝現(xiàn)貨,可看貨可提供拍照
SHORT
23412
BGA/23+
提供一站式配單服務(wù)
SHORT
5000
BGA/22+
一站式配單,只做原裝
SHORT
41101
BGA/-
大量現(xiàn)貨,提供一站式配單服務(wù)
SHORT
8000
BGA/22+
原裝現(xiàn)貨,配單能手
中,等待語音壓縮線程取出并處理。錄音函數(shù)形式如下: dx_reciottdata (activechdev,&chinfo [activechdev].iott,&tptrec[0],&xpbvox,mode); 該函數(shù)的輸入?yún)?shù)的含義如下: int chdev 語音通道的設(shè)備句柄 dx_iott *iott 指向語音數(shù)據(jù)目的地的指針 dv_tpt *tptp 指向終止參數(shù)塊的指針 dx_xpb *xpbp 指向i/o傳輸塊的指針 unsigned short mode 錄音所采取的方式 iott是一種dx_iott類型的數(shù)據(jù)結(jié)構(gòu),該數(shù)據(jù)結(jié)構(gòu)中的io_type可取值io_dev和io_mem,分別用于指定語音數(shù)據(jù)存入文件還是存入緩沖區(qū)中。io_type的另一類取值可為io_cont,io_link或dx_iott,用于指定語音數(shù)據(jù)目的地的結(jié)構(gòu)。如果io_type取值io_dev,則io_fhandle的值應(yīng)為一個(gè)文件的句柄;如果io_type取值io_mem,則io_fhandle的值應(yīng)為0,此時(shí),io_bufp指向存放語音數(shù)據(jù)的緩沖區(qū)的起始地
e(d,a,t)*(a)=(*(a)<<8)^(t)[(*(a)>>8)^(d)]; #define crcupdate16(d,a,t)*(a)=(*(a)>>8^(t)[(*(a)^(d))&0x00ff]) /* 以上兩個(gè)宏可以代替函數(shù)crcupdate和crcrevupdate */ #include #include #include /* 函數(shù)crchware是傳統(tǒng)的crc算法,其返回值即crc值 */ unsigned short crchware(data,genpoly,accum) unsigned short data;/* 輸入的數(shù)據(jù) */ unsigned short genpoly;/* crc除數(shù) */ unsigned short accum;/* crc累加器值 */ { static int i; data<<=8; for(i=8;i>0;i--) { if((data^accum)&0x8000) accum=
* trans_start記錄最后一次成功發(fā)送的時(shí)間??梢杂脕泶_定硬件是否工作正常。*/ unsigned long trans_start; /* time (in jiffies) of last tx */ unsigned long last_rx; /* time of last rx */ /* flags里面有很多內(nèi)容,定義在include/linux/if.h里。*/ unsigned short flags; /* interface flags (a la bsd) */ unsigned short family; /* address family id (af_inet) */ unsigned short metric; /* routing metric (not used) */ unsigned short mtu; /
譯器工作特點(diǎn)的基礎(chǔ)上來實(shí)現(xiàn)代碼優(yōu)化。代碼的優(yōu)化方法較多,本文針對(duì)函數(shù)優(yōu)化方法進(jìn)行闡述。 1 函數(shù)局部變量的數(shù)據(jù)類型 局部變量包括函數(shù)內(nèi)局部變量、函數(shù)參數(shù)、函數(shù)返回值。由于arm數(shù)據(jù)操作都是32位,即使數(shù)據(jù)本身只需要8位或16位,對(duì)于這三類局部變量也應(yīng)盡可能使用32位的數(shù)據(jù)類型int或long,以提高代碼執(zhí)行效率。下面以簡單求和函數(shù)為例進(jìn)行分析。 函數(shù)add1計(jì)算包含10個(gè)字的數(shù)組array的累加和,add2與add1功能相同,只是將函數(shù)add1的參數(shù)array類型改為16位的short,函數(shù)內(nèi)局部變量i類型改為8位的char,sum改為16位的short。add1、add2的c源代碼如下: int add1(int *array){ unsigned int i; int sum=0; for(i=0;i<10;i++) sum=sum+array[i]; return sum; } short add2(short *array){ char i; short sum=0; for(i=0;i<1
d { private int recbufsize; private audiorecord audiorecord; public recordthread(audiorecord audiorecord, int recbufsize) { this.audiorecord = audiorecord; this.recbufsize = recbufsize; } public void run() { try { short[] buffer = new short[recbufsize]; audiorecord.startrecording();// 開始錄制 while (isrecording) { // 從mic保存數(shù)據(jù)到緩沖區(qū) int bufferreadresult = audiorecord.read(buffer, 0, recbufsize); short[] tmpbuf = new short[bufferreadresult / ratex]
dividual grayscale clock input. gs, dc, and bc data are accessible via a serial interface port. dc and bc can be programmed via a dedicated serial interface port. the tlc5951 has three error detection circuits for led open detection (lod), led short detection (lsd), and thermal error flag (tef). lod detects a broken or disconnected led while lsd detects a shorted led. tef indicates an over-temperature condition. 2、tps61500 說明:the tps61500 is a monolithic switching regulator with integrate
加1會(huì)使其變?yōu)?。而實(shí)際上,現(xiàn)代32位處理器是不會(huì)執(zhí)行上述的那種8位加法,而是進(jìn)行32位數(shù)值的加法。因此,如果一個(gè)unsigned char的本地變量進(jìn)行加法,編譯器必須使用多條指令進(jìn)行運(yùn)算以保證加法后的符號(hào)擴(kuò)展。因此,針對(duì)各種變量尤其是循環(huán)索引的變量,應(yīng)該盡量多的在可以的地方使用int型變量。 另外,許多嵌入式處理器有16位乘法指令,而缺少32位乘法指令。在這種情況下,32位乘法將被仿效執(zhí)行,一般情況下都是很慢的。如果數(shù)據(jù)被執(zhí)行乘法操作并且計(jì)算結(jié)果不會(huì)超過16位的精度,那么就使用short或者unsigned short變量。 7. 不要用不直接的調(diào)用 這是通過包含傳遞參數(shù)的函數(shù)指針的調(diào)用,因?yàn)槟菚?huì)產(chǎn)生不可預(yù)知的邊際效應(yīng)(比如修改全局變量),使得優(yōu)化難以進(jìn)行。 8. 編寫返回?cái)?shù)值的函數(shù)而不是返回指針的函數(shù) 9. 傳遞變量時(shí)使用數(shù)值而不是指針或者全局變量 傳遞大結(jié)構(gòu)的數(shù)據(jù)時(shí),才使用指針。每個(gè)通過數(shù)值被傳遞的結(jié)構(gòu)都應(yīng)該在函數(shù)調(diào)用入口處被完全拷貝存儲(chǔ)過。 10. 使用變量的地址會(huì)使程序性能降低 因?yàn)楸镜刈兞康牡刂窌?huì)引起混淆,這如同全局變量一樣。 11. 用c
面下,按“transformer test”對(duì)應(yīng)鍵,再按“test condition”對(duì)應(yīng)鍵進(jìn)入測(cè)量參數(shù)設(shè)定畫面。用方向鍵將光標(biāo)移至所需設(shè)置的項(xiàng)目上,輸入測(cè)試頻率,測(cè)試電壓等參數(shù),并將所設(shè)項(xiàng)目勾選,按“meas/display”鍵,返回主畫面。 7)將測(cè)試線接入測(cè)試座,再將測(cè)試夾子分開一定距離,按“open”鍵, 再按“single freq”鍵,最后按“start/trigger”鍵進(jìn)行單點(diǎn)開路歸零,結(jié)束后顯示“pass”,按“start/trigger”鍵退出。將測(cè)試線夾子對(duì)夾,按“short”鍵進(jìn)行單點(diǎn)短路歸零(方法同開路歸零)。開路短路單頻點(diǎn)歸零操作完成后,亦可選擇進(jìn)行多頻點(diǎn)歸零“mult-freq”。也可按“dcr short”鍵可對(duì)直流電阻進(jìn)行歸零。 8)上述歸零操作完成后,按“exit”對(duì)應(yīng)鍵退出,按“meas/dlsplay”鍵進(jìn)入主功能畫面,再依照6)之方法進(jìn)入測(cè)量參數(shù)設(shè)定畫面,因上面操作已對(duì)參數(shù)進(jìn)行了設(shè)定,因此可直接按“meas disp”對(duì)應(yīng)鍵進(jìn)入測(cè)試界面,此時(shí)畫面顯示值為實(shí)際測(cè)量結(jié)果。 9)如須進(jìn)行設(shè)定參數(shù)值和實(shí)際值進(jìn)行比較,可在參數(shù)設(shè)定畫面下設(shè)定好測(cè)
是指在各種操作前,為了安全考慮所應(yīng)逐一檢查的項(xiàng)目。狹義指的是在pbc 業(yè)中,客戶到現(xiàn)場(chǎng)卻對(duì)品質(zhì)進(jìn)行了解,而逐一稽查的各種項(xiàng)目。 13、continuity 連通性 指電路中(circuits)電流之流通是否順暢的情形。另有 continuity testing是指對(duì)各線路通電情況所進(jìn)行的測(cè)試,即在各線路的兩端各找出兩點(diǎn),分別以彈性探針與之做緊迫接觸(全板以針床實(shí)施之),然后施加指定的電壓 (通常為實(shí)用電壓的兩倍 ), 對(duì)其進(jìn)行"連通性試驗(yàn)",也就是俗稱的 open/short testing (斷短路試驗(yàn))。 14、coupon,test coupon 板邊試樣 電路板欲了解其細(xì)部品質(zhì),尤其是多層板的通孔結(jié)構(gòu),不能只靠外觀檢查及電性測(cè)試,還須對(duì)其結(jié)構(gòu)做進(jìn)一步的微切片 (microsectioning)顯微檢查。因此需在板邊一處或多處,設(shè)置額外的"通孔及線路"圖樣,做為監(jiān)視該片板子結(jié)構(gòu)完整性(structure integraty)的解剖切片配合試樣 (conformal coupon)。品質(zhì)特嚴(yán)者,凡當(dāng)切樣不及格時(shí),該片板子也將不能出貨
ww.silvertel.com silver(錫歐爾)代理商 公司名:walasey limited-北京 地址:room 521,block a, jinfenghe office building,8 xinjiekouwai street電話:86 010-62053391/62362728傳真:+ 86 010-6205339聯(lián)系人:sales網(wǎng)址:http://www.walasey.com 公司名:infomart asia pacific pte. ltd. 地址:89, short street#02-17 golden wall centresingapore 188216電話:65 6225-6500傳真:65 6225-6005聯(lián)系人:sales網(wǎng)址:http://www.jesons.com 公司名:旭捷電子有限公司-北京 地址:中國北京市朝陽區(qū)小營路12號(hào)亞運(yùn)花園1號(hào)樓15h電話:86-10-84648068#801 傳真:010-84629162 聯(lián)系人:sales網(wǎng)址:http://www.mitscomponent.com 公司名:旭捷電子有限公司-臺(tái)
130 khz switching frequency enables small size; very tight led constant current regulation; built-in output constant-current control with primary-side feedback for led driver;. low start-up current (10 μa typical); built-in soft start; built-in short circuit protection and output overvoltage protection; current sense resistor short protection; over-temperature protection; open circuit protection; universal input range from 85 vac to 264 vac; single-fault protection; small input bulk capaci
the circuit uses transformerless supply and no galvanic isolation! figure 1: embedded saver with lamp fixture hardware descriptionfigure 1 shows complete hardware schematic of the night light saver v6.0. the ac line was protected f1, a 1a fuse. any short circuit caused by saver's components will blow the fuse. r1 and c1 limit current to the +5v zener diode, d3. r2 discharges capacitor c1 when power terminal of the circuit was opened. the super capacitor c2,+5v 0.01f filters dc supply. d4 acts as uni
hen adjust p1 to get 6.5v at the output of regulator u6.2. next first adjust p2 to get the 13.1v at the output of regulator u7, make sure transistor t5 is off or temporarily connect the t5 base to ground using test clips.3. now temporarily short the collector of transistor t5 to ground using test clips.3. adjust p3 to get the 12.1v at the output of u7 regulator ic. figure 1: circuit diagram of flash programmer v3.0figure 2 shows the circuit diagram of the interface adapter card required
路類型分類上屬于斬波電路。 figure 1. application circuit for 2-cells battery supply figure 2. application circuit for li-ion battery supply typical applications circuit rt9911,pdf datasheet (6 channel dc/dc converters) note : bottom pad is gnd pad, can be short to pin 6 (gnd)。 please remove q2 when use async boost and remove d5 when use sync boost. 來源:qick
assemble by soldering the components to the pads indicated. keep coil, resistor, and capacitor leads as short as possible. the coils should be 3/16" to 1/4" above the board and separate turns by one wire diameter. bend leads to form a little mounting foot for soldering to the circuit board. tuning and power output are affected by the distance between the coil turns, you can make fine adjustments by either spreading or compressing the coil slightly. the area surrounding the pads is ground. c
0x06#define xmodem_nak 0x15#define xmodem_can 0x18#define xmodem_eof 0x1a#define at91c_base_ncs0 0x10000000 //ncs0全部16位訪問#define at91c_base_sdram 0x20000000 extern void at91f_dbgu_printk(char *buffer);void delayms(unsigned short time) //ms等級(jí)定時(shí),time=1..1000{ unsigned short piv; piv=32768*time/1000; at91c_base_st->st_pimr=piv; while (!(at91c_base_st->st_sr&at91c_st_pits));}unsigned short at91f_crc16(char *ptr, int count) { int crc = 0;
hharm-study-2410-r1 的linux dm9000x.c驅(qū)動(dòng)中低8位反序的問題?dm9000的代碼在一開始就#undef outb #undef outw#undef inb #undef inw在重新定義#define swap_hardwareinline void outw(unsigned short value, unsigned long addr){#ifndef swap_hardware unsigned char a,b=0;unsigned short c=data(value); int i,j=7,k=1,m=128;a=c & 0x00ff; for(i=1;i<=4;i++) { b=b|((a&k)<>j); k*=2; m/=2; j--; j--; } *(volatile unsigned shor
輸出地址時(shí)片選輸出怎么不變?我用的是smartarm2200的開發(fā)板,在連接lcd(192*64)調(diào)試時(shí),按照硬件連接定義地址:#define cwadd1 (*((volatile unsigned short *) 0x83800000)) //寫指令代碼地址(左)#define cradd1 (*((volatile unsigned short *) 0x83800002)) //讀狀態(tài)字地址(左)#define dwadd1 (*((volatile unsigned short *) 0x83800004)) //寫顯示數(shù)據(jù)地址(左)#define dradd1 (*((volatile unsigned short *) 0x83800006)) //讀顯示數(shù)據(jù)地址(左)#define cwadd2 (*((volatile unsigned short *) 0x83800008)) //寫指令代碼地址(中)#define cradd2
高手板幫忙,ads編譯時(shí)出錯(cuò)編譯時(shí)提示ansi c forbids bit fieldtype 'unsigned short'union huffquad { struct { unsigned short final : 1; unsigned short bits : 3; unsigned short offset : 12; } ptr; struct { unsigned short final : 1; unsigned short hlen : 3; unsigned short v : 1; unsigned short w : 1; unsigned short x : 1; unsigned short y : 1; } value; unsigned short final : 1;};
oard\flash\flashos.h"#include "board\memorytest.h"int i, j;unsigned char tmp;unsigned char *ptr;unsigned char buf[4*1024];// 檢查外部flash, 返回 0 = 沒有錯(cuò)誤// 非0 = 出錯(cuò)的地址int checkflash (void){ int i, page; unsigned short *ptr1; ptr1 = (unsigned short *)buf; for(i=0; i<2*1024; i++) ptr1[i] = (unsigned short)i; if(erasechip_flash()) return 1; for(page=0; page<512; page++) { programpage_flash(0x81000000+page*4096, 4096, buf);