28140 Parallax Inc, 28140 Datasheet
28140
Specifications of 28140
Related parts for 28140
28140 Summary of contents
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... Two easy-to-use versions: Serial interface for microcontrollers and USB for direct connection to PC, Macintosh, or Linux machines Bi-color LED for visual indication of status Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) Web Site: www.parallax.com Forums: forums.parallax.com Sales: sales@parallax.com Technical: support@parallax ...
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... Note: Type Input Output Power Ground Use the following example circuit for connecting the Parallax RFID Card Reader: Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) Function System power. +5V DC input. Module enable pin. Active LOW digital input. Bring this pin LOW to enable the RFID reader and activate the antenna ...
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... COM port’s DTR line. Checking the DTR box in the toolbar will activate the RFID Card Reader. Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) Function Serial output to host. 2400 bps, 8 data bits, no parity, 1 stop bit. ...
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... Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) Unique ID Unique ID ...
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... Due to the fact that passive tags do not have their own transmitter and must reflect their signal Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) Test Conditions ...
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... Revision History ]------------------------------------------------ ' -----[ I/O Definitions ]------------------------------------------------- SYMBOL Enable = 0 SYMBOL SYMBOL Spkr = 2 SYMBOL Latch = 3 ' -----[ Constants ]------------------------------------------------------- SYMBOL LastTag = 2 ' -----[ Variables ]------------------------------------------------------- Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) ' low = reader on ' serial from reader ' speaker output ' lock/latch control ' 3 tags v2.2 3/22/2010 Page ...
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... IF char <> tag7 THEN Bad_Char pntr = tagNum * READ pntr, char IF char <> tag8 THEN Bad_Char pntr = tagNum * READ pntr, char Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) ' RFID bytes buffer ' from EEPROM table ' pointer to char in table ' character from table ...
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... BS2, BS2E, BS2PE T1200 CON 813 T2400 CON 396 Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) ' all match -- good tag ' groan ' for testing ' remove latch ' beep ' restore latch ' low = reader on ' serial from reader ...
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... VAR Byte(10) #ELSE chkChar VAR Byte #ENDIF tagNum VAR Nib Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340 1.0 (time adjust 1.0 (freq adjust 0.265 ' x 1 0.665 ' x 6. 0.166 ' does module have SPRAM? ' RFID bytes buffer ...
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... GOSUB Show_Name HIGH Latch FREQOUT Spkr, 2000 */ TmAdj, 880 */ FrAdj LOW Latch GOTO Main Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) ' tag byte index ' character from table ' valid tags ' turn of RFID reader ' lock the door! ' activate the reader ...
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... READ idx, char IF (char = 0) THEN EXIT DEBUG char idx = idx + 1 LOOP RETURN Copyright © Parallax Inc. RFID Card Reader Serial & USB (#28140 / 28340) ' point to first character ' read character from name ' if 0, we're done ' otherwise print it ' point to next character v2.2 3/22/2010 Page ...