EP0072471A2
Expired / Lapsed
EP
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Keyboard unit control system
Assignee: Toshiba Corp
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Filing: 1982-07-29
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Granted: —
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Expires: 2002-07-29
Abstract
Abstract A keyboard unit control system having a port (11) which includes a block selection register (18) for specifying one of a plurality of blocks of scanning lines and a scanning data selection register (17) for specifiying one of the scanning lines of the corresponding block. The scanning data and block data are supplied to a keyboard unit (2) through the scan line selecting logic (13). When the operator depresses a key on the keyboard unit (2), the key is detected by an interrupt detector (14) and a detection signal is supplied to a CPU (1). The CPU (1) first scans the blocks and then scans the scanning lines in the corresponding block.
Inventors
- 👤 Takatoshi Ishii
- 👤 Osamu Touyama
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 08:19
CPC Classifications
G; G06; G06F; G06F3/00; G06F3/01; G06F3/02; G06F3/023; H; H03; H03M; H03M11/00; H03M11/20
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
119 words
A keyboard unit control system which connects a keyboard unit (2) to a central processing unit (1) through a system bus (4), characterized by comprising: latch means (11) for latching scanning data supplied from said central processing unit (1), the scanning data including block selection data to select one of a plurality of scanning blocks each comprised of scanning lines and scanning line selection data to determine one of the scanning lines in the selected scanning block; and scan line selecting logic means (13), connected to said latch means (11) and said keyboard unit (2), for selectively supplying the scanning data to said keyboard unit (2) on the basis of the scanning data supplied from said latch means (11).
Claim 2
Dependent Claim
119 words
A keyboard unit control system which connects a keyboard unit (2) to a central processing unit (1) through a system bus (4), characterized by comprising: latch means (11) for latching scanning data supplied from said central processing unit (1), the scanning data including block selection data to select one of a plurality of scanning blocks each comprised of scanning lines and scanning line selection data to determine one of the scanning lines in the selected scanning block; and scan line selecting logic means (13), connected to said latch means (11) and said keyboard unit (2), for selectively supplying the scanning data to said keyboard unit (2) on the basis of the scanning data supplied from said latch means (11).
Claim 3
Dependent Claim
52 words
A system according to claim 1, further comprising interrupt detecting means (14), connected to said keyboard unit (2) and said central processing unit (1), for performing an interrupt operation of said central processing unit (1) on the basis of data returned from said keyboard unit (2) when the operator depresses a key.
Claim 4
Dependent Claim
50 words
A system according to claim 1, characterized in that scanning performed is static scanning, and said central processing unit (1) controls said latch means (11) and said scan line selection logic means (13) by first scanning in units of blocks and then scanning the scanning lines within the selected block.
Claim 5
Dependent Claim
27 words
A system according to claim 1, characterized in that said interrupt detecting means (14) has gate means (51) for gating return data from said keyboard unit (2).
Claim 6
Dependent Claim
54 words
A system according to claim 1, characterized in that said scan line selecting logic means (13) comprises a plurality of gate blocks (21 to 24, 31 to 34, 41 to 44) each of which has one input terminal receiving the block selection data and the other input terminal receiving the scanning line selection data.
References Cited (Backward Citations)
No citation records indexed.
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