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diff --git a/specs/dpms.xml b/specs/dpms.xml new file mode 100644 index 0000000..f504ab7 --- /dev/null +++ b/specs/dpms.xml @@ -0,0 +1,567 @@ +<?xml version="1.0" encoding="UTF-8" ?> +<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.3//EN" + "http://www.oasis-open.org/docbook/xml/4.3/docbookx.dtd" +[ +<!ENTITY % defs SYSTEM "defs.ent"> %defs; +]> + +<book id="dpms"> + +<bookinfo> + <title>X Display Power Management Signaling (DPMS) Extension Protocol Specification</title> + <subtitle>X Project Team Standard</subtitle> + <authorgroup> + <author> + <firstname>Rob </firstname><surname>Lembree</surname> + <affiliation><orgname>Digital Equipment Corporation</orgname></affiliation> + <email>lembree@zk3.dec.com</email> + </author> + </authorgroup> + <releaseinfo>X Version 11, Release &fullrelvers;</releaseinfo> + <releaseinfo>Version 1.0</releaseinfo> + <copyright><year>1996</year><holder>Digital Equipment Corporation</holder></copyright> + +<legalnotice> +<para> +Permission to use, copy, modify, distribute, and sell this +documentation for any purpose is hereby granted without fee, +provided that the above copyright notice and this permission +notice appear in all copies. Digital Equipment Corporation +makes no representations about the suitability for any purpose +of the information in this document. This documentation is +provided “as is” without express or implied warranty. +</para> + +</legalnotice> +</bookinfo> + +<chapter id="Overview"> +<title>Overview</title> +<para> +This extension provides X Protocol control over the VESA Display +Power Management Signaling (DPMS) characteristics of video boards +under control of the X Window System.<footnote> +<para> +<emphasis remap='I'>X Window System</emphasis> is a trademark of The Open Group. +</para> +</footnote> +</para> + + +<para> +<!-- .LP --> +Traditionally, the X Window System has provided for both blanking and +non-blanking screen savers. Timeouts associated with these built-in +screen saver mechanisms are limited to idle (dwell) time, and a change +timeout that specifies the change interval for non-blanking screen savers. +</para> +<para> +<!-- .LP --> +The United States' Environmental Protection Agency (EPA) Energy Star program +requires that monitors power down after some idle time by default. +While it is possible to simply overload the existing screen saver timeouts, +this solution leaves the non-privileged user little to no control over +the DPMS characteristics of his or her system. For example, disabling +DPMS would require some unintended side effect in the core screen saver, +such as disabling the changing of a non-blanking screen saver. Providing +clients with this control requires an extension to the core X Window System +Protocol, and this extension seeks to fill this gap. +</para> +<para> +<!-- .LP --> +The design goal of the DPMS extension is to be a logical extension to +the traditional screen saver. The protocol and sample implementation is +designed to use the same date types and time units as the screen saver. +The sample implementation works independently from the screen saver so that +policy as it pertains to the interaction between screen saver and DPMS can +be deferred to the user or screen saver application. The extension has +been tested with and shown to work correctly with both the internal blanking +and non-blanking screen savers, as well as with screen saver extension +clients. +</para> +<para> +The DPMS extension is designed to be simple, yet export sufficient +VESA DPMS information to enable full function clients to be written. +Included is the ability to sense DPMS capability, set and get DPMS timeouts, +enable and disable individual DPMS modes, enable and disable DPMS (without +destroying timeout values), and sense current DPMS on/off state and +power level. +</para> +<para> +There are four power levels specified by the Video Electronics Standards +Association (VESA) Display Power Management Signaling (DPMS) standard. +These are: +</para> + +<literallayout class="monospaced"> +<function>DPMS Extension Power Levels</function> + 0 DPMSModeOn In use + 1 DPMSModeStandby Blanked, low power + 2 DPMSModeSuspend Blanked, lower power + 3 DPMSModeOff Shut off, awaiting activity +</literallayout> + +<para> +It is logical to assume that successive DPMS modes be chronologically +at the same time or later than one another, and the protocol is designed +to enforce this rule. +</para> + +<para> +Note however that a concious decision is made to decouple the timeouts +associated with screen saver from the DPMS timeouts. While it might be +considered logical to require that the first non-zero DPMS timeout be +greater than or equal to the screen saver timeout, this is intentionally +omitted, leaving this policy decision to the user or the screen saver +application. In the case of a laptop where power may be scarce, the +importance of power savings should supersede the screen saver. If the +laptop user plugs the unit in and power is no longer a scarce commodity, +it may be decided to make DPMS less aggressive, or disable it completely. +</para> +</chapter> + +<chapter id="Requests"> +<title>Requests</title> +<para> +<olink targetdoc='dpmslib' targetptr='DPMSGetVersion'><function>DPMSGetVersion</function></olink> +</para> + +<informaltable frame="none"> + <?dbfo keep-together="always" ?> + <tgroup cols='1' align='left' colsep='0' rowsep='0'> + <colspec colname='c1' colwidth="1.0*"/> + <tbody> + <row> + <entry> +<emphasis remap='I'>client_major_version</emphasis>: CARD16 + </entry> + </row> + <row> + <entry> +<emphasis remap='I'>client_minor_version</emphasis>: CARD16 + </entry> + </row> + <row> + <entry>=></entry> + </row> + <row> + <entry> +<emphasis remap='I'>server_major_version</emphasis>: CARD16 + </entry> + </row> + <row> + <entry> +<emphasis remap='I'>server_minor_version</emphasis>: CARD16 + </entry> + </row> + </tbody> + </tgroup> +</informaltable> + +<para> +If supplied, the <emphasis remap='I'>client_major_version</emphasis> and +<emphasis remap='I'>client_minor_version</emphasis> indicate what version +of the protocol the +client wants the server to implement. The server version numbers +returned indicate the protocol this extension actually supports. This +might not equal the version sent by the client. An implementation can +(but need not) support more than one version simultaneously. The +<emphasis remap='I'>server_major_version</emphasis> and the +<emphasis remap='I'>server_minor_version</emphasis> are a +mechanism to support future revisions of the Display Power Management +Signaling protocol which may be necessary. In general, the major version +would increment for incompatible changes, and the minor version would +increment for small, upward-compatible changes. Servers that support the +protocol defined in this document will return a +<emphasis remap='I'>server_major_version</emphasis> +of one (1), and a <emphasis remap='I'>server_minor_version</emphasis> +of one (1). +</para> + +<para> +<olink targetdoc='dpmslib' targetptr='DPMSCapable'><function>DPMSCapable</function></olink> +</para> + +<informaltable frame="none"> + <?dbfo keep-together="always" ?> + <tgroup cols='1' align='left' colsep='0' rowsep='0'> + <colspec colname='c1' colwidth="1.0*"/> + <tbody> + <row> + <entry>=></entry> + </row> + <row> + <entry> +<emphasis remap='I'>capable</emphasis>: BOOL + </entry> + </row> + </tbody> + </tgroup> +</informaltable> + +<para> +This request is used to determine whether or not the currently running +server's devices are capable of DPMS operations. The truth value of this +request is implementation defined, but is generally based on the capabilities +of the graphic card and monitor combination. Also, the return value in the +case of heterogeneous multi-head servers is implementation defined. +</para> + +<para> +<olink targetdoc='dpmslib' targetptr='DPMSGetTimeouts'><function>DPMSGetTimeouts</function></olink> +</para> + +<informaltable frame="none"> + <?dbfo keep-together="always" ?> + <tgroup cols='1' align='left' colsep='0' rowsep='0'> + <colspec colname='c1' colwidth="1.0*"/> + <tbody> + <row> + <entry>=></entry> + </row> + <row> + <entry> +<emphasis remap='I'>standby_timeout</emphasis>: CARD16 + </entry> + </row> + <row> + <entry> +<emphasis remap='I'>suspend_timeout</emphasis>: CARD16 + </entry> + </row> + <row> + <entry> +<emphasis remap='I'>off_timeout</emphasis>: CARD16 + </entry> + </row> + </tbody> + </tgroup> +</informaltable> + +<para> +This request returns the current values of the DPMS timeout values. All +values are in units of seconds. +</para> + +<para> +<emphasis remap='I'>standby_timeout</emphasis> is the amount of time +of inactivity before standby +mode is invoked. The actual effects of this mode are implementation defined, +but in the case of DPMS compliant hardware, it is implemented by shutting off +the horizontal sync signal, and pulsing the vertical sync signal. Standby +mode provides the quickest monitor recovery time. Note also that many +monitors implement this mode identically to suspend mode. A value of +zero indicates that this mode is disabled. +</para> + +<para> +<emphasis remap='I'>suspend_timeout</emphasis> is the amount of time +of inactivity before the second +level of power savings is invoked. Suspend mode's physical and electrical +characteristics are implementation defined, but in DPMS compliant hardware, +results in the pulsing of the horizontal sync signal, and shutting off of +the vertical sync signal. Suspend mode recovery is considered to be slower +than standby mode, but faster than off mode, however this is monitor +dependent. As noted above, many monitors implement this mode identically to +standby mode. A value of zero indicates that this mode is disabled. +</para> + +<para> +<emphasis remap='I'>off_timeout</emphasis> is the amount of time of +inactivity before the third and +final level of power savings is invoked. Off mode's physical and electrical +characteristics are implementation defined, but in DPMS compliant hardware, +is implemented by shutting off both horizontal and vertical sync signals, +resulting in the power-down of the monitor. Recovery time is implementation +dependant, but frequently is similar to the power-up time of the monitor. A +value of zero indicates that this mode is disabled. +</para> + +<para> +<olink targetdoc='dpmslib' targetptr='DPMSSetTimeouts'><function>DPMSSetTimeouts</function></olink> +</para> + +<informaltable frame="none"> + <?dbfo keep-together="always" ?> + <tgroup cols='1' align='left' colsep='0' rowsep='0'> + <colspec colname='c1' colwidth="1.0*"/> + <tbody> + <row> + <entry> +<emphasis remap='I'>standby_timeout</emphasis>: CARD16 + </entry> + </row> + <row> + <entry> +<emphasis remap='I'>suspend_timeout</emphasis>: CARD16 + </entry> + </row> + <row> + <entry> +<emphasis remap='I'>off_timeout</emphasis>: CARD16 + </entry> + </row> + <row> + <entry>=></entry> + </row> + </tbody> + </tgroup> +</informaltable> + + +<para> +All values are in units of seconds. +<emphasis remap='I'>standby_timeout</emphasis> is the amount of +time of inactivity before standby mode will be invoked. This is the +lightest level of power savings, and the monitor is generally immediately +ready upon detection of user activity. This is most often implemented by +shutting off the horizontal sync signal to the monitor. +A value of zero disables this mode. +</para> + +<para> +The <emphasis remap='I'>suspend_timeout</emphasis> specifies the amount +of time of inactivity +before the screen is placed into suspend mode. Suspend mode is the +middle level of power savings, resulting in a slightly longer recovery +upon detection of activity. Suspend mode is most often implemented by +pulsing the horizontal sync signal, and removing the vertical sync +signal. A value of zero disables this mode. +</para> + +<para> +The <emphasis remap='I'>off_timeout</emphasis> specifies the amount of +time of inactivity before +the monitor is shut off. Off mode is the deepest level of power management, +resulting in the greatest power savings and the longest recovery time. +Off mode is most often implemented by removing both the horizontal and +vertical signals. A value of zero disables this mode. +</para> +<para> +The values of successive power levels must be greater than or equal +to the value of the previous (non-zero) level. A BadValue error is generated +if an illegal combination is detected. +</para> +<para> +<olink targetdoc='dpmslib' targetptr='DPMSEnable'><function>DPMSEnable</function></olink> +</para> +<para> +=> +</para> + +<para> +This request enables the DPMS characteristics of the server, using the +server's currently stored timeouts. If DPMS is already enabled, no change is +effected. +</para> + +<para> +<olink targetdoc='dpmslib' targetptr='DPMSDisable'><function>DPMSDisable</function></olink> +</para> +<para> +=> +</para> + +<para> +This request disables the DPMS characteristics of the server. It does +not affect the core or extension screen savers. If DPMS is already +disabled, no change is effected. This request is provided so that DPMS +may be disabled without damaging the server's stored timeout values. +</para> + +<para> +<olink targetdoc='dpmslib' targetptr='DPMSForceLevel'><function>DPMSForceLevel</function></olink> +</para> + +<informaltable frame="none"> + <?dbfo keep-together="always" ?> + <tgroup cols='1' align='left' colsep='0' rowsep='0'> + <colspec colname='c1' colwidth="1.0*"/> + <tbody> + <row> + <entry> +<emphasis remap='I'>power_level</emphasis>: CARD16 + </entry> + </row> + <row> + <entry>=></entry> + </row> + </tbody> + </tgroup> +</informaltable> + +<para> +This request forces a specific DPMS level on the server. If DPMS is +disabled, a BadMatch error is generated. If an erroneous power level +is specified, a BadValue error is returned, and the error value contains +the bad value. If the power level specified is already in effect, no +changes occur. Power Level must be one of DPMSModeOn, DPMSModeStandby, +DPMSModeSuspend or DPMSModeOff. +</para> + +<para> +<olink targetdoc='dpmslib' targetptr='DPMSInfo'><function>DPMSInfo</function></olink> +</para> + +<informaltable frame="none"> + <?dbfo keep-together="always" ?> + <tgroup cols='1' align='left' colsep='0' rowsep='0'> + <colspec colname='c1' colwidth="1.0*"/> + <tbody> + <row> + <entry>=></entry> + </row> + <row> + <entry> +<emphasis remap='I'>power_level</emphasis>: CARD16 + </entry> + </row> + <row> + <entry> +<emphasis remap='I'>state</emphasis>: BOOL + </entry> + </row> + </tbody> + </tgroup> +</informaltable> + +<para> +This request returns information about the current DPMS state of the +display. <emphasis remap='I'>state</emphasis> is one of DPMSEnabled +or DPMSDisabled. +If <emphasis remap='I'>state</emphasis> is DPMSEnabled, +<emphasis remap='I'>power_level</emphasis> is returned as one +of DPMSModeOn, DPMSModeStandby, DPMSModeSuspend or DPMSModeOff, otherwise +it is undefined. +</para> + +</chapter> + +<chapter id="Events_and_Errors"> +<title>Events and Errors</title> +<para> +No new events or errors are defined by this extension. +</para> +</chapter> + +<chapter id="Encoding"> +<title>Encoding</title> +<para> +Please refer to the X11 Protocol Encoding document as this document uses +conventions established there. +</para> + +<para> +The name of this extension is "DPMS". +</para> + +<literallayout class="monospaced"> +<olink targetdoc='dpmslib' targetptr='DPMSGetVersion'><function>DPMSGetVersion</function></olink> + 1 CARD8 opcode + 1 0 DPMS opcode + 2 2 request length + 2 CARD16 client_major_version + 2 CARD16 client_minor_version +=> + 1 1 Reply + 1 unused + 2 CARD16 sequence number + 4 0 length + 2 CARD16 server_major_version + 2 CARD16 server_minor_version + 20 unused +</literallayout> + +<literallayout class="monospaced"> +<olink targetdoc='dpmslib' targetptr='DPMSCapable'><function>DPMSCapable</function></olink> + 1 CARD8 opcode + 1 1 DPMS opcode + 2 1 request length +=> + 1 1 Reply + 1 unused + 2 CARD16 sequence number + 4 0 length + 1 BOOL capable + 23 unused +</literallayout> + +<literallayout class="monospaced"> +<olink targetdoc='dpmslib' targetptr='DPMSGetTimeouts'><function>DPMSGetTimeouts</function></olink> + 1 CARD8 opcode + 1 2 DPMS opcode + 2 1 request length +=> + 1 1 Reply + 1 unused + 2 CARD16 sequence number + 4 0 length + 2 CARD16 standby_timeout + 2 CARD16 suspend_timeout + 2 CARD16 off_timeout + 18 unused +</literallayout> + +<literallayout class="monospaced"> +<olink targetdoc='dpmslib' targetptr='DPMSSetTimeouts'><function>DPMSSetTimeouts</function></olink> + 1 CARD8 opcode + 1 3 DPMS opcode + 2 3 request length + 2 CARD16 standby_timeout + 2 CARD16 suspend_timeout + 2 CARD16 off_timeout + 2 unused +=> +</literallayout> + +<literallayout class="monospaced"> +<olink targetdoc='dpmslib' targetptr='DPMSEnable'><function>DPMSEnable</function></olink> + 1 CARD8 opcode + 1 4 DPMS opcode + 2 1 request length + => +</literallayout> + +<literallayout class="monospaced"> +<olink targetdoc='dpmslib' targetptr='DPMSDisable'><function>DPMSDisable</function></olink> + 1 CARD8 opcode + 1 5 DPMS opcode + 2 1 request length + => +</literallayout> + +<literallayout class="monospaced"> +<olink targetdoc='dpmslib' targetptr='DPMSForceLevel'><function>DPMSForceLevel</function></olink> + 1 CARD8 opcode + 1 6 DPMS opcode + 2 2 request length + 2 power_level + 0 DPMSModeOn + 1 DPMSModeStandby + 2 DPMSModeSuspend + 3 DPMSModeOff + 2 unused +=> +</literallayout> + +<literallayout class="monospaced"> +<olink targetdoc='dpmslib' targetptr='DPMSInfo'><function>DPMSInfo</function></olink> + 1 CARD8 opcode + 1 7 DPMS opcode + 2 1 request length +=> + 1 1 Reply + 1 unused + 2 CARD16 sequence number + 4 0 length + 2 power_level + 0 DPMSModeOn + 1 DPMSModeStandby + 2 DPMSModeSuspend + 3 DPMSModeOff + 1 BOOL state + 21 unused + +</literallayout> +</chapter> +</book> |