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EP 0 456 923 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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26.10.1994 Bulletin 1994/43 |
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Date of filing: 14.05.1990 |
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International Patent Classification (IPC)5: G09G 1/16 |
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Display system
Anzeigesystem
Système d'affichage
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Designated Contracting States: |
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CH DE ES FR GB IT LI NL SE |
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Date of publication of application: |
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21.11.1991 Bulletin 1991/47 |
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Divisional application: |
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94200912.7 / 0618561 |
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Proprietor: International Business Machines
Corporation |
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Armonk, N.Y. 10504 (US) |
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Inventor: |
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- Sawdon, David
Winchester,
Hampshire SO21 3EB (GB)
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(74) |
Representative: Burt, Roger James, Dr. |
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IBM United Kingdom Limited
Intellectual Property Department
Hursley Park Winchester
Hampshire SO21 2JN Winchester
Hampshire SO21 2JN (GB) |
(56) |
References cited: :
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- N.T.I.S. TECHNICAL NOTES, April 1988, pages 246, 1-2, Springfield, VA, US; "Interface
for color-video monitor"
- RESEARCH DISCLOSURE, no. 256, August 1985, page 414, disclosure no. 25643, Emsworth,
Hampshire, GB; "Monitor-type sensing circuit"
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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[0001] The present invention is related to a display system in which control data is communicated
between a computer system and a display device.
[0002] The control data includes parameters for specifying the geometry and resolution of
an image presented on the display device. In a display system comprising a raster-scanned
display device such as a Cathode Ray Tube (CRT) display device, these parameters are
determined by the rates and amplitudes of horizontal and vertical scan signals generated
for producing the raster scan by electrical circuits in the display device. In order
to generate the image, the scan signals are synchronised to video signals from a video
source such as a computer system by synchronisation (sync) pulses also generated by
the video source.
[0003] Some display devices can only operate in a single display mode in accordance with
a single set of parameters. Other display devices can be configured to operate in
any one of a number of display modes characterised by different sets of parameters.
The latter will hereinafter be referred to as multiple mode display devices. In a
display device controlled by a computer system it is desirable for the computer system
to identify the type of the display device so that appropriate video and sync signals
can be generated. Many examples of such computer systems, including the IBM PS 2 range,
comprise a video graphics adapter (VGA adapter) having an output port for connecting
video and sync signals to a display device. The VGA adapter also has logic responsive
to the manner in which identification pins in the output port are terminated when
connected to the display device. The logic identifies the type of display device connected
to the VGA adapter from these terminations.
[0004] UK Patent No.2,162,026 describes an example of a display system employing a multiple-mode
display device receiving video and sync signals from a computer system display adapter.
The display device can operate in any one of four display modes. The computer system
can be instructed to provide sync pulses of either positive or negative polarities.
Each polarity combination indicates a different display mode. The display device includes
decoding logic for configuring the display device to operate in a particular display
mode in response to predetermined sync pulse polarities.
[0005] The display systems of the prior art have the disadvantage that the display interfaces
of the prior art can identify, and therefore generate appropriate control signals
for, only a limited number different display devices. This limitation arises because
the number of pins available for display device identification and control is limited
by the physical form of the output port.
[0006] An object of the present invention is therefore to provide a display system having
a display adapter which is potentially compatible with an unlimited variety of display
devices.
[0007] In accordance with the present invention, there is now proposed a display system
comprising a display device for generating a visual output in response to a plurality
of data signals defining the data to be displayed, a display adapter circuit for generating
the data signals in a form specified by control data, the control data being unique
to the display device, an output port for transmitting the data signals from the display
adapter circuit to the display device and for transmitting the control data from the
display device to the display adapter circuit, characterised in that the display system
further comprises a non-volatile memory located in the display device for storing
the extended control data in the form of a plurality of control codes, and communication
logic for communicating the control codes between the memory and the output port in
response to command signals generated by the display adapter circuit. This has the
advantage that, since the control data such as the signal timing requirements of any
new display device can now be stored in the form of digital control codes held within
the memory of the display device, the display system programming does not require
updating every time a different display device is connected to the output port. Instead,
the display adapter can now read the new timing requirements from the memory of the
new display device for the purpose of generating video and sync signals for correctly
driving the new display device.
[0008] Preferably, the communication logic comprises a serial data link for communicating
the control code between the display device and the output port, device control logic
for communicating the control code between the memory and the serial data link, and
adapter control logic for communicating the control code between the serial data link
and the display adapter circuit. This has the advantage that, where the display system
comprises a multiple mode display device, the display adapter circuit can use the
serial link to configure the display device to operate in a desired display mode.
[0009] An example of the present invention will now be described with reference to the accompanying
drawings in which:
Figure 1 is a block diagram of a computer system incorporating a display system including
a display device;
Figure 2 is a block diagram of communication logic for for communicating display information
between the display adapter and the display device;
Figure 1 illustrates an example of a computer system incorporating a display system
having a CRT display device 88.
[0010] The computer system includes a central processing unit (CPU) 80 for executing programmed
instructions. A bus architecture 86 provides a data communication path between the
CPU 80 and other components of the display system. A read only memory (ROS) 81 provides
secure storage of data. A random access memory 82 provides temporary data storage.
Data communication with a host computer system 93 is provided by a communication adapter
85. An I/O adapter 84 enables data to pass between the bus architecture 86 and a peripheral
device such as a disk file 83. A user can operate the computer system using a keyboard
91 which is connected to the bus architecture 86 by a keyboard adapter 90. The CRT
display device 88 provides a visual output from the display system. A display adapter
92 generates video and sync signals at an output port 94 for enabling the display
device 88 to generate the visual output.
[0011] In accordance with the present invention, the display device 88 comprises a Non-Volatile
Memory (NVM) 9 for storing display information in the form of digital codes. The display
information is communicated between the display device 88 and the display adapter
92 along a serial link 3 which is controlled by communication logic 95. The serial
link 3 is separate from the lines carrying the video and sync signals from the display
adapter 92 to the display device. The communication logic 95 is divided into adapter
logic 96 and device logic 97. In operation, the adapter logic 96 initiates commands
for both reading and writing data to the NVM 9 and the device logic 97 responds accordingly.
[0012] The communication logic 95 will now be described in further detail with reference
to Figure 2. The adapter logic 96 comprises a device driver 1 for generating a command
code 21 in response to a program instruction. A first serialiser 2 translates the
command code 21 into a command bit stream 22 for a first line driver 4 to communicate
to the device logic 97 along the serial link 3. The device logic 97 comprises a second
receiver 5 for detecting the command bit stream 22. A second deserialiser 6 translates
the command bit stream 22 back into the command code 21. A command decoder 7 decodes
the command code 21 into an NVM address 8. Address space in the NVM 9 is divided into
a personality NVM 10 and a program NVM 11.
[0013] The personality NVM 10 contains identification codes for providing the display system
with a specification of the display device 88 connected to the display adapter 92.
Each identification code is stored in a different address location. The identification
codes include coded timing parameters for enabling the display adapter 92 to generate
appropriate video and sync signals. Specifically, the timing parameters include sync
pulse widths, active video periods, and blanking intervals. Preferably, the identification
codes also include a coded transfer parameter for indicating the maximum rate at which
the device logic 97 can read or write data to the serial link 3. By reading the transfer
parameter before issuing any further commands, the adapter logic 96 can ensure that
data is subsequently transferred between the display device 88 and the display adapter
92 at a rate which is compatible with both the adapter logic 96 and the device logic
97. Each timing parameter is stored in the form of a sixteen bit identification code.
Fifteen bits of the code specify the value of the timing parameter and the sixteenth
bit specifies the polarity. It will be appreciated that less critical timing parameters
may be stored in the form of eight bit codes or less. The personality NVM stores several
sets of timing parameters corresponding to different display modes of the display
device.
[0014] The program NVM 11 stores control codes for instructing a display input/output (I/O)
circuit 12 to adjust drive signals generated by drive circuitry 13 in the display
device. Examples of such drive signals directly affect the height, width, and brightness
of the visual ouput from the display device 88. Each control code is stored in a different
address location. By instructing the display I/O circuit 12 with appropriate control
codes, the visual output of the display device 88 can be switched between different
display modes under the control of a computer program. Preferably the program NVM
11 also stores control codes for instructing the display I/O circuit 12 to generate
sample codes representative of drive signal magnitudes at predetermined nodes of the
drive circuitry 13. It will be appreciated that such control codes may be used to
automate diagnostic methods for testing the operation of the display device 88 after
manufacture or repair.
[0015] When the adapter logic 96 issues a read command, the device logic 97 responds by
placing an appropriate response code 23 on the serial link 3. The response code 23
may either be an identification code 20 from the personality NVM or a sampled data
code 19 from the display I/O circuit 12 depending on the nature of the read command.
For implementing such a response, the device logic 97 comprises parity logic 14 for
adding a parity bit to the response code 23. A second serialiser 15 translates the
response code 23 into a response bit stream 24. The response bit stream 24 is placed
on the serial link 3 by a second line driver 16. In the display adapter 92, a first
receiver 17 detects the response bit stream 24 on the serial link 3. A first deserialiser
18 translates the detected response bit stream 24 back into the response code 23 which
is decoded by the device driver 1.
[0016] The first serialiser and the first deserialiser of the adapter logic can be combined
in a single integrated circuit module, and a similar module can be used to implement
the second serialiser and the second deserialiser. The first line driver and the first
receiver can also be incorporated in a single integrated module, and a similar driver/receiver
module can be used to implement the second line driver and the second receiver.
[0017] The adapter logic 96 can be configured to receive a response from the device logic
97 in either a "Handshaking" mode or a "Data-streaming" mode. In the "Handshaking"
mode, the device logic 97 waits for the adaptor logic to place an acknowledgement
code on the serial link 3 before sending the next byte of the response. In the "Data-streaming"
mode, the device logic 97 waits for the adapter logic 96 to acknowledge receiving
a block of bytes of the response before sending the next block.
[0018] An example of the present invention has been described wherein display information
is communicated between the display adapter 92 and the display device 88 by communication
logic 95 comprising a serial link 3 which is separate from the lines carrying the
video and sync signal from the display adapter 92 to the display device. It will be
appreciated however that other communication links and coding methods may be used.
Furthermore, the example of the present invention includes a raster-scanned display
device. It will be appreciated that the present invention is equally applicable to
other display devices such as Liquid Crystal Display device or vector-scanned display
devices.
1. A display system comprising
a display device (88) for generating a visual output in response to a plurality
of data signals defining the data to be displayed,
a display adapter circuit (92) for generating the data signals in a form specified
by control data identifying the display device (88),
an output port (94) for transmitting the data signals from the display adapter
circuit (92) to the display device (88) and for transmitting the control data from
the display device (88) to the display adapter circuit (92),
characterised in that the display system further comprises
a non-volatile memory (9) located in the display device (88) for storing the control
data in the form of a plurality of control codes, and
communication logic (95) for communicating a control code between the memory and
the output port (94) in response to a command signal (21) generated by the display
adapter circuit (92).
2. A display system as claimed in claim 1 wherein the communication logic comprises
a serial data link (3) for communicating the control code between the display device
and the output port,
device logic (97) located in the display device for communicating the control code
between the memory and the serial data link, and
adapter logic (96) located in the display adapter circuit for communicating the
control code between the serial data link and the display adapter circuit.
3. A display system as claimed in claim 2 wherein the adapter logic comprises a first
serialiser for translating a command signal (21) into a command bit stream (22), a
first line driver connected to the output port for communicating the command bit stream
(22) to the device logic along the serial link, a first receiver connected to the
output port for receiving a control bit stream from the device logic along the serial
link, and a first deserialiser for translating the control bit stream into a control
code corresponding to the command signal (21),
and wherein the device logic comprises a second receiver for receiving the command
bit stream (22) from the output port along the serial link, a second deserialiser
for translating the command bit stream (22) into the command signal (21), a command
decoder for translating the command signal (21) into a memory address for accessing
the stored control code, a second serialiser for translating the control code into
the control bit stream, a second line driver connected for communicating the control
bit stream to the output port along the serial link.
4. A display system as claimed in claim 3 wherein the first serialiser and the first
deserialiser are combined in a single integrated circuit module, and wherein the second
serialiser and the second deserialiser are combined in a single integrated circuit
module.
5. A display system as claimed in claim 4 wherein the first line driver and the first
receiver are incorporated in a single integrated circuit module, and wherein the second
line driver and the second receiver are incorporated in the a single integrated circuit
module.
6. A display system as claimed in claim 2 and further comprising means for configuring
the display device to operate in different display modes in response to mode control
signals communicated from the adapter logic to the device logic along the serial link.
7. A display system as claimed in claim 2 or claim 6 and further comprising means for
adjusting operating parameters of drive circuitry of the display device in response
to parameter control signals communicated from the adapter logic to the device logic
along the serial link.
8. A display system as claimed in claim 7 and further comprising means for obtaining
digital samples of signals at nodes of the drive circuitry and for communicating the
samples from the device logic to the adapter logic along the serial link in response
to a data request signal communicated from the adapter logic to the device logic along
the serial link.
9. A display system as claimed in any preceding claim wherein the control codes stored
in the memory include digitally encoded data signal timing parameters for the display
device.
10. A computer system comprising a display system as claimed in any preceding claim.
11. A computer system for connection to a display device (88), the computer system comprising:
a display adaptor circuit (92) for generating data signals in a form specified
by control data identifying the display device to produce a visual output on the display
device (88); and
an output port (94) for transmitting the data signals from the display adaptor
circuit (92) to the display device (88) and for transmitting control data from the
display device (88) to the display adaptor circuit (92); characterised in that the
display adaptor circuit (92) includes: adaptor logic means (96) to send, via the output
port (94), a command signal to the display device (88), and to receive from the display
device (88), via the output port (94), the control data, in the form of a plurality
of control codes, sent from the display device (88) in response to the command signal.
1. Ein Anzeigesystem, das folgendes umfaßt:
eine Anzeigeeinheit (88) zur Generierung einer Bilddatenausgabe in Antwort auf eine
Vielzahl von Datensignalen, welche die anzuzeigenden Daten definieren,
eine Bildschirmadapterschaltung (92) zur Generierung der Datensignale in einer Form,
die von Steuerdaten spezifiziert wird, welche für die Anzeigeeinheit (88) kennzeichnend
sind,
einen Ausgangsanschluß (94) zum Übermitteln der Datensignale von der Bildschirmadapterschaltung
(92) an die Anzeigeeinheit (88) und zum Übermitteln der Steuerdaten von der Anzeigeeinheit
(88) an die Bildschirmadapterschaltung (92),
dadurch gekennzeichnet, daß das Anzeigesystem weiterhin folgendes umfaßt:
einen in der Anzeigeeinheit (88) befindlichen, nichtflüchtigen Speicher (9) zum Speichern
der Steuerdaten in Form einer Vielzahl von Steuercodes, und
Übertragungslogik (95) zur Übertragung eines Steuercodes zwischen dem Speicher und
dem Ausgabeanschluß (94) in Antwort auf ein Befehlssignal (21), das von der Bildschirmadapterschaltung
(92) generiert wird.
2. Ein Anzeigesystem wie in Anspruch 1 niedergelegt, in dem die Übertragungslogik folgendes
umfaßt:
eine serielle Datenverbindung (3) zum Übertragen des Steuercodes zwischen der Anzeigeeinheit
und dem Ausgangsanschluß,
in der Anzeigeeinheit befindliche Einheitenlogik (97) zur Übertragung des Steuercodes
zwischen dem Speicher und der seriellen Datenverbindung, und
in der Bildschirmadapterschaltung befindliche Adapterlogik (96) zur Übertragung des
Steuercodes zwischen der seriellen Datenverbindung und der Bildschirmadapterschaltung.
3. Ein Anzeigesystem wie in Anspruch 2 niedergelegt, in dem die Adapterlogik einen ersten
Serializer zur Umsetzung eines Befehlssignals (21) in einen Befehlsbitstrom (22) umfaßt,
einen ersten an den Ausgangsanschluß angeschlossenen Leitungstreiber zur Übertragung
des Befehlsbitstroms (22) an die Einheitenlogik über die serielle Verbindung, einen
ersten, an den Ausgangsanschluß angeschlossenen Empfänger zum Empfang eines Steuerbitstroms
von der Einheitenlogik über die serielle Verbindung, und einen ersten Deserializer
zur Umsetzung des Steuerbitstroms in einen Steuercode, der dem Befehlssignal (21)
entspricht,
und bei dem die Einheitenlogik einen zweiten Empfänger zum Empfang des Befehlsbitstroms
(22) vom Ausgangsanschluß über die serielle Verbindung umfaßt, sowie einen zweiten
Deserializer zur Umsetzung des Befehlsbitstroms (22) in das Befehlssignal (21), einen
Befehlsdecoder zur Umsetzung des Befehlssignals (21) in eine Speicheradresse für den
Zugriff auf den gespeicherten Steuercode, einen zweiten Serializer zur Umsetzung des
Steuercodes in den Steuerbitstrom, und einen zweiten angeschlossenen Leitungstreiber,
der den Steuerbitstrom über die serielle Verbindung an den Ausgangsanschluß überträgt.
4. Ein Anzeigesystem wie in Anspruch 3 niedergelegt, bei dem der erste Serializer und
der erste Deserializer in einem einzelnen integrierten Schaltkreismodul kombiniert
sind, und bei dem der zweite Serializer und der zweite Deserializer in einem einzelnen
integrierten Schaltkreismodul kombiniert sind.
5. Ein Anzeigesystem wie in Anspruch 4 oder Anspruch 5 offenbart, bei dem der erste Leitungstreiber
und der erste Empfänger in einem einzelnen integrierten Schaltkreismodul zusammengefaßt
sind, und bei dem der zweite Leitungstreiber und der zweite Empfänger in einem einzelnen
integrierten Schaltkreismodul zusammengefaßt sind.
6. Ein Anzeigesystem wie in Anspruch 2 offenbart, das weiterhin Mittel zum Konfigurieren
der Anzeigeeinheit für den Betrieb in verschiedenen Anzeigemodi in Antwort auf Modussteuersignale
umfaßt, die von der Adapterlogik über die serielle Verbindung an die Einheitenlogik
übertragen werden.
7. Eine Anzeigeeinheit wie in Anspruch 2 oder Anspruch 6 niedergelegt, die weiterhin
Mittel zum Anpassen der Betriebsparameter von Ansteuerschaltungen der Anzeigeeinheit
in Antwort auf Parametersteuersignale umfaßt, die von der Adapterlogik über die serielle
Verbindung an die Einheitenlogik übertragen werden.
8. Eine Anzeigeeinheit wie in Anspruch 7 offenbart, die weiterhin Mittel zum Abrufen
von digitalen Signalabtastwerten an Knoten der Ansteuerschaltungen und zum Übertragen
der Abtastwerte von der Einheitenlogik über die serielle Verbindung zur Adapterlogik
in Antwort auf ein Datenanforderungssignal umfaßt, welches von der Adapterlogik über
die serielle Verbindung an die Einheitenlogik übertragen wird.
9. Ein Anzeigesystem wie in einem der vorstehenden Ansprüche niedergelegt, bei dem die
im Speicher abgelegten Steuercodes digital verschlüsselte Signalzeitsteuerungsparameter
für die Anzeigeeinheit enthalten.
10. Ein Computersystem, das ein Anzeigesystem wie in einem der vorstehenden Ansprüche
niedergelegt umfaßt.
11. Ein Computersystem für den Anschluß an eine Anzeigeeinheit (88), wobei das Computersystem
folgendes umfaßt:
eine Anzeigeadapterschaltung (92) zur Erzeugung von Datensignalen in einer Form, die
von Steuerdaten spezifiziert wird, die für die Anzeigeeinheit kennzeichnend sind,
um eine visuelle Ausgabe auf der Anzeigeeinheit (88) zu erzeugen; und
einen Ausgangsanschluß (94) für die Übertragung der Datensignale von der Anzeigeadapterschaltung
(92) zur Anzeigeeinheit (88) und für die Übertragung von Steuerdaten der Anzeigeeinheit
(88) zur Anzeigeadapterschaltung (92); dadurch gekennzeichnet, daß die Anzeigeadapterschaltung
(92) folgendes umfaßt: Adapterlogikmittel (96), um über den Ausgangsanschluß (94)
ein Befehlssignal an die Anzeigeeinheit (88) zu senden und um von der Anzeigeeinheit
(88) über den Ausgangsanschluß (94) die Steuerdaten in Form einer Vielzahl von Steuercodes
zu empfangen, die von der Anzeigeeinheit (88) in Antwort auf das Befehlssignal gesendet
werden.
1. Système d'affichage comprenant
un dispositif d'affichage (88) pour générer une sortie visuelle en réponse à une pluralité
de signaux de données définissant les données à afficher,
un circuit adaptateur d'affichage (92) pour générer les signaux de données sous une
forme spécifiée par des données de contrôle identifiant le dispositif d'affichage
(88),
un port de sortie (94) pour transmettre les signaux de données du circuit adaptateur
d'affichage (92) au dispositif d'affichage (88) et pour transmettre les données de
contrôle du dispositif d'affichage (88) au circuit adaptateur d'affichage (92),
caractérisé en ce que le système d'affichage comporte en outre
une mémoire non volatile (9) disposée dans le dispositif d'affichage (88) pour mémoriser
les données de contrôle sous la forme d'une pluralité de codes de contrôle, et
une logique de communication (95) pour communiquer un code de contrôle entre la mémoire
et le port de sortie (94) en réponse à un signal de commande (21) généré par le circuit
adaptateur d'affichage (92).
2. Système d'affichage tel que revendiqué dans la revendication 1, dans lequel la logique
de communication comprend un lien de données série (3) pour communiquer le code de
contrôle entre le dispositif d'affichage et le port de sortie,
une logique de dispositif (97) disposée dans le dispositif d'affichage pour communiquer
le code de contrôle entre la mémoire et le lien de données série et
une logique d'adaptateur (96) disposée dans le circuit adaptateur d'affichage pour
communiquer le code de contrôle entre le lien de données série et le circuit adaptateur
d'affichage.
3. Système d'affichage tel que revendiqué dans la revendication 2, dans lequel la logique
d'adaptateur comprend un premier sérialiseur pour traduire un signal de commande (21)
en un flux de bits de commande (22), un premier circuit de pilotage de ligne connecté
au port de sortie pour communiquer le flux de bits de commande (22) à la logique de
dispositif sur le lien série, un premier récepteur connecté au port de sortie pour
recevoir un flux de bits de contrôle de la logique de dispositif sur le lien série,
et un premier désérialiseur pour traduire le flux de bits de contrôle en un code de
contrôle correspondant au signal de commande (21),
et dans lequel le dispositif logique comprend un second récepteur pour recevoir le
flux de bits de commande (22) du port de sortie sur le lien série, un second désérialiseur
pour traduire le flux de bits de commande (22) en un signal de commande (21), un décodeur
de commande pour traduire le signal de commande (21) en une adresse mémoire pour accéder
au code de contrôle mémorisé, un second sérialiseur pour traduire le code de contrôle
en flux de bits de contrôle, un second circuit de pilotage de ligne connecté pour
communiquer le flux de bits de contrôle au port de sortie sur le lien série.
4. Système d'affichage tel que revendiqué dans la revendication 3, dans lequel le premier
sérialiseur et le premier désérialiseur sont combinés en un module de circuit intégré
unique, et dans lequel le second sérialiseur et le second désérialiseur sont combinés
en un module de circuit intégré unique.
5. Système d'affichage tel que revendiqué dans la revendication 4 ou la revendication
5, dans lequel le premier circuit de pilotage de ligne et le premier récepteur sont
incorporés dans un module de circuit intégré unique, et dans lequel le second circuit
de pilotage de ligne et le second récepteur sont incorporés dans un module de circuit
intégré unique.
6. Système d'affichage tel que revendiqué dans la revendication 2, comprenant en outre
des moyens pour configurer le dispositif d'affichage pour fonctionner dans des modes
d'affichage différents en réponse à des signaux de contrôle de mode communiqués par
la logique d'adaptateur à la logique de dispositif sur le lien série.
7. Dispositif d'affichage tel que revendiqué dans la revendication 2 ou la revendication
6, comprenant en outre des moyens pour ajuster les paramètres de fonctionnement du
circuit de pilotage du dispositif d'affichage en réponse à des signaux de contrôle
de paramètre communiqués par la logique d'adaptateur à la logique de dispositif sur
le lien série.
8. Dispositif d'affichage tel que revendiqué dans la revendication 7, et comprenant en
outre des moyens pour obtenir des échantillons numériques de signaux à des noeuds
du circuit de pilotage et pour communiquer les échantillons de la logique de dispositif
à la logique d'adaptateur sur le lien série en réponse à un signal de demande de données
communiqué par la logique d'adaptateur à la logique de dispositif sur le lien série.
9. Système d'affichage tel que revendiqué dans l'une quelconque des revendications précédentes,
dans lequel les codes de contrôle stockés dans la mémoire incluent des paramètres
de synchronisation de signal de données numériquement encodés pour le dispositif d'affichage.
10. Système d'ordinateur comprenant un système d'affichage tel que revendiqué dans l'une
quelconque des revendications précédentes.
11. Système d'ordinateur pour la connexion à un dispositif d'affichage (88), le système
d'ordinateur comprenant :
un circuit adaptateur d'affichage (92) pour générer des signaux de données sous une
forme spécifiée par des données de contrôle identifiant le dispositif d'affichage
pour produire une sortie visuelle sur le dispositif d'affichage (88) ; et
un port de sortie (94) pour transmettre les signaux de données du circuit adaptateur
d'affichage (92) au dispositif d'affichage (88) et pour transmettre des données de
contrôle du dispositif d'affichage (88) au circuit adaptateur d'affichage (92) ; caractérisé
en ce que le circuit adaptateur d'affichage (92) inclut : des moyens de logique d'adaptateur
(96) pour envoyer, par l'intermédiaire du port de sortie (94), un signal de commande
au dispositif d'affichage (88), et pour recevoir du dispositif d'affichage (88), par
l'intermédiaire du port de sortie (94), les données de contrôle, sous la forme d'une
pluralité de codes de contrôle, envoyés à partir du dispositif d'affichage (88) en
réponse au signal de commande.