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Wavecom GR64 Application Note
Summary of GR64
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Application note gr/gs64 uart sleep protocols reference: wi_dev_gx64_apn_001 version: 001 date: 2006/11/09.
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The information contained in this document is the proprietary information of wavecom inc. The contents are confidential and any disclosure to persons other than the officers, employees, agents or subcontractors of the owner or licensee of this document, without the prior written consent of wavecom i...
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Revision history edition change information first first edition second implemented document review comments third added description of “three-wire” sleep mode and wake-up application note gr/gs64 uart sleep protocols page: 3/26 this document is the sole and exclusive property of wavecom. Not to be d...
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Contents 1 introduction............................................................................................ 6 2 standby handshaking ............................................................................. 7 2.1 uart 1 signal description......................................................
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4 autonomous standby and embedded applications................................ 23 5 examining sleep mode .......................................................................... 24 5.1 purpose.............................................................................................................
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1 introduction low power operation is crucial for applications where power consumption must be carefully controlled or limited. Gr/gs64 wireless cpu®s achieve significant power savings by reducing clock rates or eliminating clocks to internal components during idle periods. In the following descript...
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2 standby handshaking standby handshaking can be used when all uart signal lines are connected between the host and wireless cpu®. This method cannot be used by embedded applications. When enabled, the host and wireless cpu® use modem control lines in addition to receive and transmit to coordinate w...
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Implemented. Although not every signal is explicitly referenced to uart 1 it is nevertheless implicit. All of the signals shown in the table above as required need appropriate hardware connectivity and software support in the host application. Figure 1. Typical host – wireless cpu® uart1 interface 2...
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A further level of flow-control is provided by the data-terminal-ready and data-set- ready signals. These signals are instrumental in activating the sleep and wake-up mechanisms. The uart1 signals described in this document are referenced to the gr/gs64 system connector. The signal amplitudes are de...
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2.1.2.4 cts1 (clear to send) [wireless cpu® ⇒ host] output signal used to control data flow from the host uart to the wireless cpu® uart. When hardware flow control is enabled, cts1 is held low by the wireless cpu® to indicate its readiness to accept data from the host. The wireless cpu® holds the c...
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2.1.2.7 ri (ring indicator) [wireless cpu® ⇒ host] output signal used as an alert from the wireless cpu® to the host to request attention. The ring indicator is used to inform the host that the wireless cpu® has something to communicate. The ri could be activated for • an incoming voice call • an in...
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This results in significant power reduction. Typically a drx8 paging mode may consume less than 2ma. This mode is often referred to as sleep mode. In order to conserve the maximum amount of current, the uarts (as well as other normally active circuitry) also assume a low power state. The interface w...
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2.4.1 host initiated sleep this example shows a sequence of events from initial power-up of the wireless cpu® to the first sleep activation, in this case initiated by the host uart. Figure 2. Sequence of events from initial power-up to first sleep activation time description 1 the wireless cpu® is u...
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2.4.2 host initiated wake-up in this example the uarts are in a sleep mode and the host initiates a wake-up. Figure 3. Host initiating wake-up to uarts in sleep mode time description 1 the uart interface is inactive, the wireless cpu® and host may be in a sleep (low power) state at this point in tim...
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2.4.3 wireless cpu® initiated sleep the example shows a similar situation to section 2.4.1, where the wireless cpu® is going through its initial power-up. After exchanging some data the wireless cpu® initiates sleep. The host responds within the time-out period a . Figure 4. Wireless cpu® initiates ...
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2.4.4 wireless cpu® initiated wake-up in this example the uart interfaces are in sleep mode and the wireless cpu® initiates a wake-up . Figure 5. Uarts in sleep mode, wireless cpu® initiates wake-up time description 1 the uart interface is inactive, the wireless cpu® and host may be in a sleep (low ...
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2.4.5 wireless cpu® repeats attempts to initiate sleep in this example, the wireless cpu® attempts to initiate sleep through the normal flow control mechanism, but the host fails to acknowledge within the time-out period for repeated attempts. Figure 6. Wireless cpu® attempts sleep initiation, host ...
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2.4.6 dsr1 timing two time periods are significant in the functioning of dsr: figure 7. Dsr functioning time periods period a : this is fixed in the gr/gs64 application to 500ms, the time-out period for the host to respond to a sleep request from the wireless cpu®. Period b : this is programmable by...
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2.4.8 incoming mt event during sleep if an incoming mobile terminated voice or circuit-switched data call is received the wireless cpu® will assert ri (ring indicator). If an sms message is received and the sms ri function is enabled (using the at command at*e2smsri) it will also toggle the ring ind...
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3 autonomous standby 3.1 purpose like standby handshaking, autonomous standby enables the wireless cpu® to enter low power mode during idle periods. However, instead of using the uart signal lines to request or acknowledge sleep mode, the wireless cpu® enters sleep mode without host interaction, or ...
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1. Network activity. In drx mode (see section 2.3), the wireless cpu® awakens at each expected network frame that may contain a notification of activity for the wireless cpu®. Such notifications include incoming calls, sms messages or interrogations. Network activity causes the wireless cpu® to awak...
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3.5 the inactivity delay once the wireless cpu® is awake, the inactivity delay allows you to communicate with the wireless cpu® without having to disable autonomous standby. Each message sent or received by the wireless cpu®’s uart restarts the inactivity delay. For instance, you might process a rec...
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4 autonomous standby and embedded applications your embedded applications can also enable or disable autonomous standby by using the spm() function. If autonomous standby is enabled, dlys() or dlyms() will cause the wireless cpu® to enter low power mode for the period of the delay. The following exa...
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5 examining sleep mode 5.1 purpose sleep mode can be enacted by either the wireless cpu® or the host at any time. The primary purpose for enabling sleep mode is to conserve energy (current consumption). This feature is particularly useful for applications which power the wireless cpu® through a batt...
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5.3 key considerations it is important for you to note the mechanisms that enable or disable sleep mode, which may also help you to identify the reason why sleep is not being enacted (or poorly implemented) in your application. • sleep is enabled and disabled by at command or embedded applications f...
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Gr/gs64 uart sleep protocols page: 26/26 application note this document is the sole and exclusive property of wavecom. Not to be distributed or divulged without prior written agreement. Ce document est la propriété exclusive de wavecom. Il ne peut être communiqué ou divulgué à des tiers sans son aut...