r8 antenna

code to the beginning of the probe function:int *ptest = NULL;*ptest = 0x1234;Re-compile the kernel, and it will error after startup and print out the following Oops information:Unable to handle kernel NULL pointer dereference in virtual Address 00000000PGD = c0004000[00000000] *pgd=00000000Internal error:oops:805 [#1]Modules Linked In:cpu:0Not tainted (2.6.22.6 #36)PC is at s3c2410fb_probe+0x18/0x560LR is at platform_drv_probe+0x20/0x24PC: [LR: [psr:a0000013Sp:c0481e64 ip:c0481ea0 fp:c0481e9cr

Q: No line from the living room, but in the bedroom signal is relatively weak, what is the solution? A: No line by the signal strength and the route itself, the receiver's wireless network card, the use of distance, the middle interval of the number of load-bearing walls, and so on, and even with the neighbor's home without the number of lines are also related. Method One: Antenna gain Normally, no line from through a load-bearing wall

wireless network card between the best to see, as far as possible to avoid the wall between them, especially the load-bearing wall (reinforced concrete wall). We know that in order to reduce the radiation on the human body, the power of the wireless router is generally small, so the use of the process is very much in the vicinity of electronic equipment interference, so in the setting of wireless router placement, we must remember to stay away from microwave ovens, refrigerators and other house

multi-dimensional transmission scheme: one single RF channel is used to send and receive two or more signal streams. As a result, the wireless communication system can transmit data twice or more in a channel. In the system, use more than one high-integration RF upconverter) and antenna to transmit these multiple signals, and there is also more than one high-integration RF downconverter) and the antenna to

channel. In this way, all users use the channel in the default configuration of the router, which is prone to channel interference. If nearby neighbors use the same channel as ours, our wireless signals will be affected. We can also use the Network Stumbler software for scanning to see which wireless signals exist nearby and which channel is used. Then modify our own wireless channels to avoid duplication with other channels. In addition, you should note that the signal of a channel will interf

. In this way, all users use the channel in the default configuration of the router, which is prone to channel interference. If nearby neighbors use the same channel as ours, our wireless signals will be affected. We can also use the Network Stumbler software for scanning to see which wireless signals exist nearby and which channel is used. Then modify our own wireless channels to avoid duplication with other channels. In addition, you should note that the signal of a channel will interfere with

channel in the default configuration of the router, which is prone to channel interference. If nearby neighbors use the same channel as ours, our wireless signals will be affected. We can also use the Network Stumbler software for scanning to see which wireless signals exist nearby and which channel is used. Then modify our own wireless channels to avoid duplication with other channels. In addition, you should note that the signal of a channel will interfere with two adjacent channels at the sa

one, human factors The distance between the wireless router and the network card is too long, in this case can only be solved by a different configuration of the appropriate antenna. The wireless router and the network card have the obstacle influence, sometimes also can cause the disconnection breakdown, for instance the indoor complex environment, the wall, the furniture influence. So try not to go through walls over three floors as much as possib

realized by using multiple circuits and packet switching connections on a single terminal. You can support business with different quality requirements, such as voice and packet data, and ensure high quality and perfect coverage. (2) High spectrum efficiency. WCDMA can efficiently use the radio spectrum. Since it uses single cell multiplexing, frequency planning is not required. The network capacity can be greatly improved by using the layered cell structure, adaptive

unsigned int32 and cause overflowexception when overflow occurs. Conv. ovf. u4.un Convert the unsigned value at the top of the computing stack to unsigned int32 and cause overflowexception when overflow occurs. Conv. ovf. u8 Converts the signed value at the top of the computing stack to unsigned int64, and causes overflowexception when overflow occurs. Conv. ovf. u8.un Convert the unsigned value at the top of the computing stack to unsigned int6

implementation.Arch/arm/include/uapi/asm/unistd.h#define __NR_OABI_SYSCALL_BASE 0x900000#if defined(__thumb__) || defined(__ARM_EABI__)#define __NR_SYSCALL_BASE 0#else#define __NR_SYSCALL_BASE __NR_OABI_SYSCALL_BASE#endif#define __NR_mmap (__NR_SYSCALL_BASE+ 90)#define __NR_munmap (__NR_SYSCALL_BASE+ 91)#define __NR_mmap2 (__NR_SYSCALL_BASE+192)Arch/arm/kernel/entry-common. S /*============================================================================= * SWI ha

them is configured, the system only allows the old Abi method by default, but the old_syscall_table does not exist, function calling will be completed through sys_call_table. Refer to the following code.It is useful for our projects. .align 5 ENTRY(vector_swi) sub sp, sp, #S_FRAME_SIZE stmia sp, {r0 - r12} @ Calling r0 - r12 add r8, sp, #S_PC stmdb r8, {sp, lr}^ @ Calling sp, lr mrs

UE or editplus, and add at last: (E/android-ndk-r8-windows/android-ndk-r8 is the path to install ndk)Ndk_root =/cygdrive/e/android-ndk-r8-windows/android-ndk-r8Export ndk_root The specific meaning is as follows:That is, whether the login user under your current window is admin. if not, the folder with your login name will be generated in the cygwin \ home \ di

frame pointer to the value of the stack pointer (SP)–push the preserved registers to the stack–make Space for local storageA example might look like this:Push {R4-R7, LR}//Save LR, R7, R4-r6add R7, SP, #12//adjust R7 to point to saved R7push {r8, R10, R11}// Save remaining GPRs (R8, R10, R11) Vstmdb sp!, {d8-d15}//Save vfp/advanced SIMD Registers d8sub sp, SP, #36//AL Locate space for local

, #0x17 @ angel_swireason_entersvc ARM (Swi 0x123456) @ angel_swi_arm THUMB (svc 0xab) @ angel_swi_thumbNot_angel:Mrs R2, CPSR @ turn off interrupts to Orr R2, R2, #0xc0 @ Prevent Angel from running MSR cpsr_c, R2#else teqp pc, #0x0c000003 @ tur N Off Interrupts#endifIf the kernel runs from Angel into a mode of USR mode, it will need to enter the SVC mode and disable all Fiq and IRQ interrupts. These are only performed when the user mode is entered. Normally, the code that closes the interrupt i

. Extended antenna enhancement Signal Because the antenna gain size directly affects the signal transmission strength and receiving capability, some routers on the market use detachable antennas, therefore, replacing a high-gain antenna with a wireless router is the most direct method to enhance the signal. The gain antenna