HT82K28 Holtek Semiconductor Inc, HT82K28 Datasheet
HT82K28
Related parts for HT82K28
HT82K28 Summary of contents
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... Supports Japanese DOS/V 106-key · keyboard · Supports code set 1, for PS/2 model 30 keyboard General Description The HT82K28A is a keyboard encoder espe- cially designed for IBM PC/AT, IBM PS/2 and all compatible machines. The HT82K28A accepts keyboard inputs and contains a 16-character first-in-first-out buffer Pin Assignment HT82K28A Win98 Keyboard Encoder · ...
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... Note: These are stress ratings only. Stresses exceeding the range specified under ²Absolute Maxi- mum Ratings² may cause substantial damage to the device. Functional operation of this device at other conditions beyond those listed in the specification is not implied and prolonged expo- sure to extreme conditions may affect device reliability. HT82K28A Description Input Voltage.................V -0. Operating Temperature ..................0° ...
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... Input Low Voltage (DATA, CLOCK) V Input High Voltage IH Output Low Voltage (R0~R18 Output Low Voltage (DATA, CLOCK) Internal Pull-high Resistance (C0~C7 Internal Pull-high Resistance (CLOCK, DATA) f System Clock SYS HT82K28A Test Conditions Min. Typ. Max. Unit 4.75 5 5.25 ¾ ¾ ¾ 2 ¾ 0 ¾ 0.6 ¾ 0 ¾ ...
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... Functional Description The HT82K28A basic function is to detect key press and release activity and to transmit the corresponding scan code, as well as make and break codes to the system. The device also accepts commands from the sys- tem and responds to the system if necessary. All ...
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... Make/break ¨ Make ¨ Typematic/make/break ¨ HT82K28A All keys except PAUSE are typematic. Typematic means that the KB keeps send- ing make codes if the key is held down. The data report is according to the typematic rate/delay: Default values are: delay 500ms ± 20% 10.9 char/sec ± ...
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... Stop scanning and wait for further instruc- ¨ tion · Echo - EE Send the system ¨ Continue scanning if the keyboard is en- ¨ abled Note: This command does not need to feed back the ACK HT82K28A mode 1 mode 2 mode ...
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... Set key type - FB,FC, Set key type - Typematic ¨ Set key type - Make/Break ¨ HT82K28A FD : Set key type - Make ¨ The keyboard responds with ACK, clears its ¨ output buffer and prepares to receive key identification Key identification is accomplished by the ¨ ...
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... If the keyboard "data" line is found inactive level following the 10th bit, a frame error has occurred, and the keyboard contin- ues to count until the "data" line becomes ac- tive. The keyboard then makes the "data" line inactive and sends a Resend. 8 HT82K28A February 16, 2000 ...
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... Note: The parity bit is either and the 8 data bits, plus the parity bit, always have an odd number HT82K28A 9 February 16, 2000 ...
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... HT82K28A Key Number Make/Break Code ...
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... +Left-Shift +Right-Shift E0 37 /E0 B7 +Ctrl Break Windows Virtual Key HT82K28A Num Lock / / / / ...
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... HT82K28A Key Number Make/Break Code ...
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... F0 7C Base +Ctrl Break Windows Virtual Key N N N/A 13 HT82K28A Num Lock ...
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... F0 43 Typematic Typematic Typematic Typematic Typematic Typematic Make/Break HT82K28A Make/ Default Key Key # Note Break Code Make/Break Make/Break Make/Break Typematic 62 ...
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... F0 5E 124 125 126 131 132 133 Win Win APP HT82K28A Default Key State * Make Only * Typematic * Make Only * Make Only * Make Only * Make Only * Make Only * Make Only * ...
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... Timing Diagrams Data output Keyboard data input HT82K28A February 16, 2000 ...
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... Application Circuits HT82K28A February 16, 2000 ...
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... ENTER F11 BS \ NUM SPACE NUM 1 NUM 4 LOCK NUM / NUM 0 NUM 2 NUM 5 NUM * NUM . NUM 3 NUM 6 UP NUM K107 Arrow ENTER R-SHF L-SHF L-WIN R-WIN 18 HT82K28A C0 PAUSE SCR LOCK K14 NUM 7 NUM 8 NUM 9 NUM + WAKE UP K130 February 16, 2000 ...
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... The above key code is according to the Microsoft specification except for the following keys. Key No Code Set 1 Make/Break 109 78 F8 129 F1 130 F0 Code Set 2 Make/Break Code Set 3 Make/Break HT82K28A February 16, 2000 ...
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... Holtek reserves the right to alter its products without prior notification. For the most up-to-date information, please visit our web site at http://www.holtek.com.tw. HT82K28A 20 February 16, 2000 ...