Bus Faults with setting LCD Display TFT

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 18, 2016 by lpcware
Content originally posted in LPCWare by Weizhong-YANG on Fri May 27 06:50:19 MST 2016
Hi sirs,

We are working on new design about CPU card which include core cortex M3 LPC1850FET180. We meet a problem.
Description of ours system
THE CPU is  composed of :
1 Microcontrôler : LPC1850FET180
1 Spifi flash : S25FL032P (4 M) (code)
1 SDRAM : MT48LC4M16A2P_6A (8 M)
1 Flash parallel 32Mb: SST39VF3201B-70
Driving of display LCD TFT 5,7” (640 X 480)
Display memory LCD 0x28000000-0x2812C000 (SDRAM)
Graphics library emWin SEGGER V.524
Option for File GUIConf.c :
Memory Assignment :
Code/Const : default
Zero Initialized Data : RAM2[0x2812D000-0x283FFFFF] (SDRAM)
Other Data: RAM2[0x2812D000-0x283FFFFF] (SDRAM)
Encountered problem:
It’s occurs when we set a program for driving display.
(However, a testing program of the SDRAM in writing and reading on 8bits, 16bits et 32 bits works without fault)
program is blocked in the proceedings GUI_Init() (emWin SEGGER)
which jumps to « BusFault_Handler » with Bus Faults : IMPRECISERR.

If we set GUIConf.c to the RAM :
   Option for File GUIConf.c :
Memory Assignment :
Code/Const : default
Zero Initialized Data : IRAM2 [0x20000000-0x2000FFFF]
Other Data: IRAM2 [0x20000000-0x2000FFFF]

GUI_Init() works without problem.
But with fonctions GUI_SetBkColor(GUI_RED);
We get:  Bus Faults : PRECISERR, BFARVALID,
BUS_FAULT_ADDR: 0x1A7F4A7C/ 0x000002DF/ 0xB0022F34/……,

We use the following tools
Infos sur MDK Microcontroller Development Kit : µVision 5 :
µVision V5.14.0.0
Copyright (C) 2015 ARM Ltd and ARM Germany GmbH. All rights reserved.

Tool Version Numbers:
Toolchain:        MDK-ARM Professional  Version:
Toolchain Path:    C:\Keil\ARM\ARMCC\Bin
C Compiler:         Armcc.exe        V5.05 update 1 (build 106)
Assembler:          Armasm.exe        V5.05 update 1 (build 106)
Linker/Locator:     ArmLink.exe        V5.05 update 1 (build 106)
Library Manager:    ArmAr.exe        V5.05 update 1 (build 106)
Hex Converter:      FromElf.exe        V5.05 update 1 (build 106)
CPU DLL:               SARMCM3.DLL          V5.14.0.0
Dialog DLL:         DCM.DLL              V1.13.1.0
Target DLL:             UL2CM3.DLL           V1.155.0.0
Dialog DLL:         TCM.DLL              V1.14.4.0

Debug avec ULINK2 KEIL

We have controled on the electronic board that we haven’t short-circuit between datas, adress, no cutted tracks
With scopemeter, signals seem corrects…

Could you help us ? ?

Thank you in advance.