外文翻譯---ds18b20單總線數(shù)字溫度計(jì)(存儲(chǔ)版)
【正文】 t serial code stored in an onboard ROM (3) Can be powered form data line. Power supply range is to (4) Measures temperatures form 55℃ to +125℃ ,177。 (9) Copy Scratchpad [48H] 這個(gè)命令把暫存器的內(nèi)容拷貝到 DS18B20 的 EEPROM 存儲(chǔ)器里，即把溫度報(bào)警觸發(fā)字節(jié)存入非易失性存儲(chǔ)器里。 （ 6） Convert T [44H] 這條命令啟動(dòng)一次溫度轉(zhuǎn)換無(wú)需其它數(shù)據(jù)。這條命令在總線上有單個(gè)或多個(gè)器件時(shí)都可以使用。溫度報(bào)警觸發(fā)器的設(shè)置寄存器都由非易失性電可擦寫存儲(chǔ)器（ EEPROM）組成，設(shè)置值可以通過相應(yīng)命令寫入，一旦寫入后不會(huì) 因?yàn)榈綦姸鴣G失。 DS18B20 的內(nèi)部結(jié)構(gòu) DS18B20 的內(nèi)部結(jié)構(gòu)如圖 1 所示。如果總線上有不止一個(gè)從機(jī)，當(dāng)所有從機(jī)試圖同時(shí)傳送信號(hào)時(shí)就會(huì)發(fā)生數(shù)據(jù)沖突。然而，只有在最近一次測(cè)溫后遇到符合報(bào)警條件的情況， DS18B20 才會(huì)響應(yīng)這條命令。 （ 8） Read Scratchpad [0BEH] 這個(gè)命令暫存器的內(nèi)容。 ℃ accuracy from 10℃ to +85℃ (5) Thermometer resolution is userselected from 9 to 12 bits (6) Converts temperature to 12bit digital word in 750ms(max) (7) Alarm search mand identifies and addresses devices whose temperature is outside of programmed limits (temperature alarm condition) (8) Available in 8pin SOIC, and 3bit TO 92 packages DS18B20 BLOCK DIAFRAM Figure 1 shows a block diagram of the DS18B20 , The 64bite ROM stores the device’s serial code. The scratchpad memory contains the 2byte temperature register that stores the digital output from the temperature sensor. In addition, the scratchpad provides access to the 1byte upper and lower alarm trigger register allows the user to set the resolution of the temperaturetodigital conversion to 9, 10, 11 or 12 bits. The TH 、 TL and configuration registers are nonvolatile(EEPROM), so they will retain data when the device is powered down. Figure 1 block diagram of the DS18B20 DS18B20 ROM COMMANDS (1) SEARCH ROM [0F0H] W
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