# Error after write in memory AMB82 **URL:** \ **Category:** SDK\ **Tags:** rtl8735b, evb-amb82\ **Created:** [March 28, 2025, 10:40pm UTC](https://forum.amebaiot.com/t/error-after-write-in-memory-amb82/3983 "2025-03-28T22:40:09Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![TeschRenan](https://avatars.discourse-cdn.com/v4/letter/t/958977/32.png) [@TeschRenan](https://forum.amebaiot.com/u/TeschRenan)\ **Post date:** [March 28, 2025, 10:40pm UTC](https://forum.amebaiot.com/t/error-after-write-in-memory-amb82/3983/1 "2025-03-28T22:40:10Z")
Hello, i try write some string in memory and during the code is executed nothing is broken, but after restart the uC i received a erro, in bellow. Basicly i write a string from 32bytes in 3 sector, 0x1E20, 0x1E40 and 0x1E60 when i received the package from BLE, in bellow my write and read function. void writeStringToMemory(const char\* str, uint32\_t addr) { int len = strlen(str) + 1; // Sum null-terminator ‘\0’ int i = 0; while (i \< len) { uint32\_t word = 0; memcpy(&word, str + i, min(4, len - i)); // Maximum 4 bytes FlashMemory.writeWord(addr + i, word); i += 4; } } void readStringFromMemory(char\* buffer, uint32\_t addr, int maxLen) { int i = 0; while (i \< maxLen) { uint32\_t word = FlashMemory.readWord(addr + i); memcpy(buffer + i, &word, min(4, maxLen - i)); // Copy back to buffer i += 4; if (buffer[i - 1] == ‘\0’) break; // Stop if find null-terminator } } The error! Boot Loader \<== == RAM Start == Build @ 17:32:16, Oct 24 2024 $8735b\>interface 0 is initialized interface 1 is initialized cfg\_size\_lib = 40, cfg\_size\_user = 40 Initializing WIFI …[Driver]: [HALMAC] 11692M HALMAC\_MAJOR\_VER = 1 HALMAC\_PROTOTYPE\_VER = 4 HALMAC\_MINOR\_VER = 20 HALMAC\_PATCH\_VER = [Driver]: The driver include MP [Driver]: Ver = libwlan:2024.10.24.17.49\_b9.6\_2e6d0195b6b821c8df060f1392ff528c46a039df RFE type = 0 start\_addr=(0x4000), end\_addr=(0x8000), buffer\_size=(0x4000), smp\_number\_max=(2048) WIFI initialized Bluetooth init BT\_ADDR in cfgbuf [40:f4:c9:12:de:bd] hci\_platform\_controller\_reset:482(info) BT Reset OK! MemManage Fault: SCB Configurable Fault Status Reg = 0x00000001 MemManage Fault Status: MemManage Fault Address Reg is invalid Instruction access violation: the processor attempted an instruction fetch from a location that does not permit execution. S-domain exception from Thread mode, Extended Stack frame on S-PSP Registers Saved to stack Stacked: R0 = 0x10004415 R1 = 0x000006c0 R2 = 0x55555555 R3 = 0x00000000 R4 = 0xf8acf001 R5 = 0x55555555 R6 = 0x55555555 R7 = 0x00000163 R8 = 0x00000000 R9 = 0x7039494c R10 = 0x10101010 R11 = 0x11111111 R12 = 0x00000016 LR = 0x7018b433 PC = 0xf8acf000 PSR = 0x41100000 Current: LR = 0xffffffed MSP = 0x20003fd8 PSP = 0x7040ad58 xPSR = 0x40000004 CFSR = 0x00000001 HFSR = 0x00000000 DFSR = 0x00000000 MMFAR = 0x00000000 BFAR = 0x00000000 AFSR = 0x00000000 PriMask = 0x00000000 SVC priority: 0x00 PendSVC priority: 0xf0 Systick priority: 0xf0 MSP Data: 20003FD8: 702992BC FFFFFFF9 20004000 000003E8 20003FE8: E000E000 702992BC 07070707 701384A5 20003FF8: 70138518 21000000 F76BC70C 54875265 20004008: FAF94FB6 F7A635E9 D6C81FF7 09FC8F24 20004018: 5AF87F3F F9BADFFD 9BFB1E4F D579BE0F 20004028: 4F9F45FA EE9AFDCC FCE5CB50 0FB22E92 20004038: F9AA73D5 F59B9FEB 19BB341C 45965E72 20004048: B067BEEF 153974DF DA06237F 175D1168 20004058: EE7FC991 97B46886 FD89DB6A 58042943 20004068: F3700B9F 4B8359BF 01346BBF 42061FC9 20004078: E82F2381 74D17518 50F94A4A 332C7C58 20004088: C7FECC2F CD2A36F4 332C7840 C8CD2238 20004098: D52EA71F BD597362 9722AFEC CA2DE83A 200040A8: DA50BFD6 3152C81D C564E129 56D8B093 200040B8: D7CDA105 6DDCADDF BE13A036 023BC67D 200040C8: 5032C0AF 88062FF8 5270E3C3 1F686392 PSP Data: 7040AD58: 10004415 000006C0 55555555 00000000 7040AD68: 00000016 7018B433 F8ACF000 41100000 7040AD78: 703EC3C0 00000000 00003C00 00004C00 7040AD88: 00000000 703EC3C0 00000011 FFFFFFFF 7040AD98: 0000000A 70194BA7 00000000 00000000 7040ADA8: 00046048 00046048 7040FF40 703CF06C 7040ADB8: 0000000A 70185867 00000000 70196BEB 7040ADC8: 00000000 55555555 00000000 00000002 7040ADD8: 00000000 703CF06C 0000000A 70196D77 7040ADE8: 00000000 00000002 703CF06C 703CF069 7040ADF8: 703EC0F4 70196F05 70196ED9 7018BD6F 7040AE08: 703F3E40 70188BB9 0000003C 703E83E0 7040AE18: 00000001 70189453 701890C1 703E83E0 7040AE28: 00000001 7028F0E5 70394988 70394951 7040AE38: 7028F0DB 7016CD71 00000003 7014526F 7040AE48: 00000012 000000DE 000000BD 05050505 == NS Dump == CFSR\_NS = 0x00000000 HFSR\_NS = 0x00000000 DFSR\_NS = 0x00000000 MMFAR\_NS = 0x00000000 BFAR\_NS = 0x00000000 AFSR\_NS = 0x00000000 MSP\_NS = 0x00000000 PSP\_NS = 0x00000000 NS HardFault Status Reg = 0x00000000 SCB Configurable Fault Status Reg = 0x00000000 No Back Trace! We have any possibility to read the core dump in this uC? Thank you ---
**Author:** ![TeschRenan](https://avatars.discourse-cdn.com/v4/letter/t/958977/32.png) [@TeschRenan](https://forum.amebaiot.com/u/TeschRenan)\ **Post date:** [April 1, 2025, 1:55pm UTC](https://forum.amebaiot.com/t/error-after-write-in-memory-amb82/3983/2 "2025-04-01T13:55:39Z")
Hello People, any response from this topic? ---
**Author:** ![Kelvin\_Huang](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.amebaiot.com/kelvin_huang/32/2130_2.png) [@Kelvin\_Huang](https://forum.amebaiot.com/u/Kelvin_Huang)\ **Post date:** [April 2, 2025, 1:49am UTC](https://forum.amebaiot.com/t/error-after-write-in-memory-amb82/3983/3 "2025-04-02T01:49:00Z")
Hi @TeschRenan, Can I check with you if you have tried our Arduino example for reading and writing the word into flash memory? Can you debug first by writing into each particular sector 1 at a time, and identify which is the sector that does not allow you to write? Thank you. ---
**Author:** ![TeschRenan](https://avatars.discourse-cdn.com/v4/letter/t/958977/32.png) [@TeschRenan](https://forum.amebaiot.com/u/TeschRenan)\ **Post date:** [April 2, 2025, 10:31am UTC](https://forum.amebaiot.com/t/error-after-write-in-memory-amb82/3983/4 "2025-04-02T10:31:24Z")
Hello Kelvin, good evening, yes i can! I wil try today. Thank you. ---
**Author:** ![TeschRenan](https://avatars.discourse-cdn.com/v4/letter/t/958977/32.png) [@TeschRenan](https://forum.amebaiot.com/u/TeschRenan)\ **Post date:** [April 2, 2025, 12:21pm UTC](https://forum.amebaiot.com/t/error-after-write-in-memory-amb82/3983/5 "2025-04-02T12:21:00Z")
Hello @Kelvin_Huang i think i found the problem, when i write anything in 0x1E20 my code break, when a jumpt this address the code works! In attach example using the 0x1E20 address and without, in my project i use BLE, will be if the problem is with BLE? This screenshot is from error. Before restart ![Screenshot_14](https://us1.discourse-cdn.com/flex016/uploads/ameba/original/2X/2/25285790e6cfd16e6a3775117ae354b3fd8bc8f2.png) After Restart. ![Screenshot_15](https://us1.discourse-cdn.com/flex016/uploads/ameba/original/2X/9/906832ce63ea8a739b007fb0c70a3217aca54fc6.png) This code with after restart jumping 0x1E20 address ![Screenshot_16](https://us1.discourse-cdn.com/flex016/uploads/ameba/original/2X/5/5b06f21a068544142c8bc3eb8041e46de4a65b6e.png) I don’t know about problem but in the time, jump 0x1E20 address works from me! Best Regards ---
**Author:** ![Kelvin\_Huang](https://sea2.discourse-cdn.com/flex016/user_avatar/forum.amebaiot.com/kelvin_huang/32/2130_2.png) [@Kelvin\_Huang](https://forum.amebaiot.com/u/Kelvin_Huang)\ **Post date:** [April 3, 2025, 1:43am UTC](https://forum.amebaiot.com/t/error-after-write-in-memory-amb82/3983/6 "2025-04-03T01:43:26Z")
Hi @TeschRenan, Maybe something has been written in that address that does not allow modification. For your use case, you just have to find a sector that is not in used to write your data into flash. Thank you. ---
**Author:** ![TeschRenan](https://avatars.discourse-cdn.com/v4/letter/t/958977/32.png) [@TeschRenan](https://forum.amebaiot.com/u/TeschRenan)\ **Post date:** [April 3, 2025, 12:30pm UTC](https://forum.amebaiot.com/t/error-after-write-in-memory-amb82/3983/7 "2025-04-03T12:30:46Z")
Hi @Kelvin_Huang, ok perfect, the AMB dont have a partition with use only to save data, in strange the microcontroller share some blocks without separated!