Manuel d'utilisation / d'entretien du produit IXP43X du fabricant Intel
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Document Nu mber: 316844; Revision: 001US Intel ® IXP43X Product Line of Network Processors Hardware De sign Guidelines April 2007.
Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 2 Document Number: 316844; Revision: 001US INFORMA TION IN THIS DOCUMENT IS PROVIDED IN CONNECTION WITH IN TEL® PRODUCTS. NO LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHE RWISE, T O ANY INTELL ECTUA L PRO PER TY RIGHT S IS GR ANTED BY TH IS DOCUMENT .
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 3 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors Contents 1.0 Introduction ......... ......... .......... ....
Intel ® IXP43X Product Line of Network Pr ocessors—Hardware De sign Guide lines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 4 Document Number: 316844; Revision: 001US 3.14 Power ... ........ ........... ........ ........... .
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 5 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 11 HSS Interface Example ......... .. ......... .. .. .. .. .
Intel ® IXP43X Product Line of Network Pr ocessors—Hardware De sign Guide lines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 6 Document Number: 316844; Revision: 001US 29 DDR Clock Timings ............. .......... ........... .
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 7 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors Revision H.
Intel ® IXP43X Product Line of Network Pr ocessors—Hardware De sign Guide lines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 8 Document Number: 316844; Revision: 001US.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 9 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 1.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 10 Document Number: 316844; Revision: 001US 1.2 Related Documentation The reader of this design guide should also be familiar with the material and concept presented in the following documents: 1.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 11 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 1.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 12 Document Number: 316844; Revision: 001US • 16 GP.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 13 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors Note: Figure 1 shows the Intel ® IXP435 Network Processor.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 14 Document Number: 316844; Revision: 001US 1.5 Typical Applications • SOHO-Small Business/Residential • Modular Router • Wireless Gateway(802.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 15 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 2.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 16 Document Number: 316844; Revision: 001US § § Figure 2.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 17 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 18 Document Number: 316844; Revision: 001US 3.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 19 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors The memory controller only corrects single bi t ECC errors on read cycles.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 20 Document Number: 316844; Revision: 001US 3.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 21 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 22 Document Number: 316844; Revision: 001US 3.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 23 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors EX_ADDR[10] IOWAIT_CS0 1 = EX_IOWAI T_N is sampled during the read/ write expansion bus cy cles for Chip Select 0.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 24 Document Number: 316844; Revision: 001US Note: The Intel XScale processor can operate at slower speeds than the factory programmed speed setting.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 25 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors Boot-str apping is required in certain address pi ns of the Expansion bus.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 26 Document Number: 316844; Revision: 001US 3.3.5 Flash Interface Figure 4 illustrates how a boot ROM is connected to the expansion bus.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 27 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.4 UART Interface The UART interface are a 16550-compliant UAR T with the exception of tr ansmit and receive buffers.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 28 Document Number: 316844; Revision: 001US •C l e a r t o S e n d Note: The UAR T module does not support full mode m functionality .
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 29 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.5 MII Interface The IXP43X network processors support a maximum of two Ethernet MACs.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 30 Document Number: 316844; Revision: 001US 3.5.1 Signal Interface MII Table 9. MII NPE A Signal Recommendations Name Type Field Pull Up/ Down Recommendations ETHA_TXCLK I Ye s Tr a n s m i t C l o c k .
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 31 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.5.2 Device Connection, MII Figure 6 is a typical example of an Ethernet PHY device interfacing to one of the MACs via the MII hardware protocol.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 32 Document Number: 316844; Revision: 001US 3.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 33 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.6.1 Signal Interface 3.6.2 Design Notes The drive strength for GPIO[15:14] is limited t o 8 mA, while GPIO [13:0] can output up to 16 mA.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 34 Document Number: 316844; Revision: 001US 3.7.1 Signal Interface Table 13. USB Host Signal Recommendations A typical implementation of a USB interface Host down-stream is sh own in Figure 9 .
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 35 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 2. If a 1.5-K Ω, pull-up resistor is connected to USB_P_NEG line, the USB port is identified as Low-speed mode.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 36 Document Number: 316844; Revision: 001US Figure 8.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 37 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.8 UTOPIA Level 2 Interface The IXP43X network processors support th e industry-standard UTOPIA Level 2 bus interface.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 38 Document Number: 316844; Revision: 001US UTP_OP_DA TA[4] / ETHA_TXEN TRI No UTOPIA Level 2 Mode of Operation: UTOPIA Level 2 output data.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 39 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors UTP_IP_ FCI I Y es UTOPIA Lev el 2 Input Data flow control input signal.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 40 Document Number: 316844; Revision: 001US UTP_IP_DA TA[5] / ETHA_COL IY e s UTOPIA Level 2 Mode of Operation: UTOP IA Level 2 input data.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 41 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.8.2 Device Connection The following example shown in Figure 10 shows a typical interface to an ADSL Framer via the UTOPIA bus.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 42 Document Number: 316844; Revision: 001US 3.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 43 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.10 SSP Interface The IXP43X network processors have a Sync hronous Serial P eripheral Interface (SSP) module.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 44 Document Number: 316844; Revision: 001US 3.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 45 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 46 Document Number: 316844; Revision: 001US 3.11.1 Signal Interface Table 17. PCI Controll er (Sheet 1 of 2) Name Type Field Pull Up/ Down Recommendations PCI_AD[31:0] I/O Y es PCI Address/Data bus.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 47 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 48 Document Number: 316844; Revision: 001US 3.11.3 PCI Option Interface The IXP43X network processors can be used in a design as a host or as an option device.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 49 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors PCI_IRDY_N I/O Connect signal to same pin between the two devices.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 50 Document Number: 316844; Revision: 001US 3.11.4 Design Notes • The IXP43X network processors do not support the 5 V PCI signal interface by itself .
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 51 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.12.1 Signal Interface 3.13 Input System Clock The IXP43X network processors require a 33.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 52 Document Number: 316844; Revision: 001US 3.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 53 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 3.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 54 Document Number: 316844; Revision: 001US 3.14.1 Decoupling Capaci tance Recom mendatio ns It is common practice to place decoupling capacitors between the supply voltages and ground.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 55 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors The IXP43X network processors can be configured at reset de- assertion via external, pull-down resistors on the address expa nsion bus signals EX_ADDR[23:21].
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 56 Document Number: 316844; Revision: 001US 4.0 General PCB Guide 4.1 PCB Overview Beginning with components selection, this chapter presents general PCB guidelines.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 57 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors • Place noisy parts (clock, processor , video , and so on.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 58 Document Number: 316844; Revision: 001US • P oor.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 59 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors • F ast and slow tr ansmission line networks must be considered •P C B - b o a r d v e l o c i t i e s •B o a r d F R 4 ~ 4 .
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 60 Document Number: 316844; Revision: 001US 5.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 61 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors • Do not place high-frequency oscillators and switching network devices close to sensitive analog circuits.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 62 Document Number: 316844; Revision: 001US Figure 20 and Figure 21 show good and poor design pr actice s for via placement on surface-mount boards.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 63 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 5.2.2 Clock Signal Co ns iderations • Provide good return current paths for clock tr aces.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 64 Document Number: 316844; Revision: 001US — Be aware of propagation delays be tween a microstrip and stripline.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 65 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors — Space within a group can be just 1 w. — Space between clock signals or clock to an y other signal should be 3 w.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 66 Document Number: 316844; Revision: 001US • Use at least one decoupling capacitor per power pin and place it as close as possible to the pin.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 67 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 6.0 PCI Interface Design Considerations The IXP43X network processors have a single, 32-bit PCI device module that runs at 33 MHz.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 68 Document Number: 316844; Revision: 001US 6.3 Clock Distribution T o meet timing and avoid clock ov erloading, it is recommended to use point -to-point clock distribution as shown in Figure 24 .
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 69 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 6.3.1 Trace Lengt h Limits Maximum trace lengths can be calculated for specific speeds at which the bus is intended to run.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 70 Document Number: 316844; Revision: 001US 6.3.2 Routing Guidelines It is recommended to route signals with respec t to an adjacent ground plane.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 71 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 7.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 72 Document Number: 316844; Revision: 001US Table 24.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 73 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors Figure 25.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 74 Document Number: 316844; Revision: 001US Table 25. Supported DDRI 32- bit SDRAM Configurations DDR SDRAM Technology DDR SDRAM Arrangement # Banks Address Size Leaf Select Total Memory Size a a.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 75 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors The DDR_RCOMP signal must be termin ated through resistors specified in Figure 26 .
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 76 Document Number: 316844; Revision: 001US 7.3 DDRII OCD Pin Requirements Figure 27 shows the requirement for the DDRRES1 and DDRRES2 pins.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 77 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors Figure 29.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 78 Document Number: 316844; Revision: 001US Figure 31. DDR - Write Pr eamble/Postamble Duration Table 30.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 79 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 7.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 80 Document Number: 316844; Revision: 001US — T abl.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 81 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors Data D_CB0 / DDR_CB0 402.94 D_CB4 / DDR_CB4 3 85.50 D_CB1 / DDR_CB1 393.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 82 Document Number: 316844; Revision: 001US 7.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 83 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 7.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 84 Document Number: 316844; Revision: 001US internal layers, ex cept for pin escapes. It is recommended that pin escape vias be located directly adjacent to the ball pads on all signals.
Intel ® IXP43X Product Line of Network Processors April 2007 HDG Document Number : 316844; Revision: 001US 85 Hardware Design Guidelines—Intel ® IXP43X Product Line of Network Processors 7.
Intel ® IXP43X Product Line of Network Processors—Hardware Design Guidelines Intel ® IXP43X Product Line of Network Proce ssors HDG April 2007 86 Document Number: 316844; Revision: 001US § § Series R esistor 2 0 Ω Nominal T race Width 1 Internal (Strip Line) 3.
Un point important après l'achat de l'appareil (ou même avant l'achat) est de lire le manuel d'utilisation. Nous devons le faire pour quelques raisons simples:
Si vous n'avez pas encore acheté Intel IXP43X c'est un bon moment pour vous familiariser avec les données de base sur le produit. Consulter d'abord les pages initiales du manuel d'utilisation, que vous trouverez ci-dessus. Vous devriez y trouver les données techniques les plus importants du Intel IXP43X - de cette manière, vous pouvez vérifier si l'équipement répond à vos besoins. Explorant les pages suivantes du manuel d'utilisation Intel IXP43X, vous apprendrez toutes les caractéristiques du produit et des informations sur son fonctionnement. Les informations sur le Intel IXP43X va certainement vous aider à prendre une décision concernant l'achat.
Dans une situation où vous avez déjà le Intel IXP43X, mais vous avez pas encore lu le manuel d'utilisation, vous devez le faire pour les raisons décrites ci-dessus,. Vous saurez alors si vous avez correctement utilisé les fonctions disponibles, et si vous avez commis des erreurs qui peuvent réduire la durée de vie du Intel IXP43X.
Cependant, l'un des rôles les plus importants pour l'utilisateur joués par les manuels d'utilisateur est d'aider à résoudre les problèmes concernant le Intel IXP43X. Presque toujours, vous y trouverez Troubleshooting, soit les pannes et les défaillances les plus fréquentes de l'apparei Intel IXP43X ainsi que les instructions sur la façon de les résoudre. Même si vous ne parvenez pas à résoudre le problème, le manuel d‘utilisation va vous montrer le chemin d'une nouvelle procédure – le contact avec le centre de service à la clientèle ou le service le plus proche.
