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(No.RA033<Rev.001>)1-63
5.2
MPU(IC901) and DDR3 (IC791) Troubleshooting
Overview : The flowchart about troubleshooting of BGA package MPU (IC901) and DDR3 (IC791) .
This flowchart describe about "error display of e7" that is meant an error occurrence when the MPU (IC901) communicate to other
MPU (IC200).
When repeater display error "e7" , we come to mind two main reason.
One reason is MPU makes trouble, the other is DDR3 makes trouble.
5.2.1 Outline for the process of MPU (901) and DDR3 (IC791) troubleshooting
The display indicates “e7”
1.Checking power supply
Voltage of MPU(IC901).
Checking DDR3 and DDR3
interface.
2.Checking Reset and Main
clock of MPU(IC901).
3.Checking NAND Flash and
boot mode of MPU(IC901).
4.Checking interface between
MPU(IC200) and MPU(IC901).