Sam4s SPS-500, Руководство по обслуживанию

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6 Troubleshooting
SAM4S SPS-500 SERIES 6-3
6-3 MAIN B’D Problem (System boot & program)
6-3-1 Boot Flash ROM (A29L800UV) problem of Main B’D
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Related RESET
→ Check the reset IC (AME8500, U19) & reset time (150 ~ 270ms).
→ Check the reset switch if it does operate correctly.
→ Check the reset signal of 74LCX14 (U17) output.
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Related System signals (Address, Data, nCE, nOE, nWE)
→ Check these signals whether it short / open.
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Related System Clock
→ Check the crystal, if it operates correctly or not.
→ Clock frequency is 16.9344MHz.
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Related Booting select DIP switch
→ For normal mode, DIP switch (SW1) must be all OFF state.
→ Check the related signal whether it short / open.
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Related boot Flash ROM program (A29L800UV)
→ If the boot program is erased during servicing, boot error is occurred.
→ Refer to chapter 3 for boot program recovery and download.
6-3-2 Application program (NAND Flash & SDRAM) problem of Main B’D
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Related System memory (SDRAM)
→ Check signals for SDRAM (U4,U12) whether it short / open.
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Related NAND Flash memory
→ This memory is used for OS & application program storage such as PC HDD.
→ If the program is erased or broken during program upgrade, boot error is occurred.
→ In this case, Perform are-download use to the sd-card or lan
→ For program download or upgrade, refer the chapter 3.