arm_开发者

How to set ARM user app start address when using USB bootloader?

Just picked up one of these ARM Cortex-M3 LPC1768 mini boards from eBay. It\'s basically a breakout board.[详细]

2023-04-13 09:42 分类：问答

ARM v7 ADD vs. LDR

Is there any difference between the following instruction (besides flags affection)? 开发者_运维知识库ADDR6, SP, #0xDC[详细]

2023-04-12 17:09 分类：问答

"Immediate out of range errors" when assigning 0.0 to a NEON register

If I understand it correctly, because ARM instructions are 32 bits long they can only hold so many bits of immediate value. What I\'m trying to do is vmov.f32 s0, #0.0, and I get \"immediate out of ra[详细]

2023-04-12 01:07 分类：问答

What is the most efficient way to set one bit of a register in ARM?

I\'m writing ARM assembly code that at some point has to set a single bit of a register to 1. This is best done of course via \"register-or-bitmask\" method. However, according to ARM documentation, t[详细]

2023-04-11 23:42 分类：问答

What is the function of the additional coprocessor register of the MRC command?

Quoting from the ARM MRC documentation, MRC{2}<c><q> <coproc>, #<opc1>, <Rt>, <CRn>, <CRm>{, #<opc2>}[详细]

2023-04-11 16:57 分类：问答

Optimizing RGBA8888 to RGB565 conversion with NEON

I\'m trying to optimize an image format conversion on iOS using the NEON vector instruction set. I assumed this would map well to that because it processes a bunch of similar data.[详细]

2023-04-11 16:28 分类：问答

Error compiling node for optware - libv8.a: could not read symbols: File in wrong format

Getting this error cross compiling node.js for optware (slug) on Ubuntu 11.10. /optware/cs05q1armel/builds/node/build/default/libv8.a(api.o): Relocations in generic ELF (EM: 3)[详细]

2023-04-11 15:43 分类：问答

compiling native GCC for arm using cross-compiler

I am looking to create a native build of GCC for an ARM system and I am running into some trouble. The build machine is i686-linux. Every tutorial I see tells me how to set up the actual cross c开发者[详细]

2023-04-11 12:43 分类：问答

AND faster than integer modulo operation?

It is possible to re-express: i % m as: i & (m-1) where, i is an unsigned integer m is a power of 2 My question is: is the AND operation any faster? Don\'t modern CPUs support integer[详细]

2023-04-11 10:46 分类：问答

Difference in benchmark with different ARM cross compilers using hardware FP and soft VFP

I am currently using Open virtual platform that simulates an ARM processor and I\'m doing some benc开发者_如何学Chmarks on a simple task started by FreeRTOS with different cross compilers.[详细]

2023-04-11 05:32 分类：问答