Newbie needs help for RS232, SPI on STM32-p103

Hi All,

I am pretty new to ARM development. I just got my STM32-P103 and ARM-USB-OCD JTAG working. I can now compile and flash a demo code that blinks an led on the board. I am using eclipse + CodeSourcery + openOCD.

First thing I want is to do is to use the development board to interface my Linux/Intel computer’s RS232 to an SPI device, so I can write and read certain register values on the SPI device. Could anyone point me some example codes, books, articles so I can get started?

Eventually I want to use the Cortex-M3 for a Kalman filter in an inertial measurement unit. The Kalman filter will need float point calculations for matrix multipilcations and matrix inversions. Is Cortex-m3 the right choice for such an application? How many flops can it reach?

Any suggestions are welcome.

Everett

I wouldn’t be concerned with the MIPS speed of the processor, but more concerned with the lack of a FPU. It does have a hardware divide, which is good, but without an FPU you’re going to be spending a lot of time (cycles) doing the required FP math.

Unfortunately, ARM may not be the best architecture of choice for this type of project, but it really depends on your requirements. If you are just doing Inertial measurements in one to three dimensions (roll/pitch/yaw) then it might be alright, if you are doing full 3-D 6DOF inertial calculations in a EKF you’ll probably be left wanting more cycles.

Yes, I want to do a full 3D 6DOF with unscented Kalman filter eventually. if arm cortex-m3 is not a good choice, what is better choice for my application then? Is arm9 or arm11 a better choice? Or some other architectures? I don’t need a lot of peripherals except 12 or 14 bit A2D, RS323, SPI, may be an USB.

Everett

You’ll want something with an FPU. Some of the freescale processors have it, otherwise there are some powerful AVR’s that might have FPU’s, I haven’t looked into it.