Search found 86 matches

by Pito
Wed Sep 09, 2020 11:50 am
Forum: Projects
Topic: SDcard Logger with FIFO and FIR Filter (FreeRtos)
Replies: 1
Views: 217

SDcard Logger with FIFO and FIR Filter (FreeRtos)

Hi folks, this is an example I shared in past (old stm32duino forum). /////////// SDcard Logger with FIFO and FIR Filter (FreeRtos) for Maple Mini or Blue Pill ================================================================== As it has been discussed in this forum, writing a continuous stream of da...
by Pito
Wed Sep 09, 2020 11:36 am
Forum: Projects
Topic: 3D Orientation Model
Replies: 1
Views: 285

Re: 3D Orientation Model

by Pito
Sat Apr 11, 2020 2:51 pm
Forum: General discussion
Topic: STM32F103RCT6 on li-ion for a week
Replies: 10
Views: 1851

Re: STM32F103RCT6 on li-ion for a week

Which core do you use?
by Pito
Sat Apr 11, 2020 2:39 pm
Forum: General discussion
Topic: STM32F103RCT6 on li-ion for a week
Replies: 10
Views: 1851

Re: STM32F103RCT6 on li-ion for a week

44mA at 72MHz is too much, imho.
25-30mA is something I would buy..
What is the board like? Any LEDs with 220ohm serial resistors?
You may run stm32 with an external 8MHz crystal without PLL engaged, you have to change the settings, however.
With 8MHz crystal you may get 5mA Idd.
by Pito
Mon Apr 06, 2020 2:56 pm
Forum: General discussion
Topic: New APM32F103CB
Replies: 44
Views: 7640

Re: New APM32F103CB

Squonk42 wrote:
Mon Apr 06, 2020 10:17 am
Good!

So, just a simple single-precision floating point ALU with Cordic exposed in peripheral address space.

No SIMD vector or MAC operations and no saturation, so almost useless for all DSP usage.

Better than nothing :-(
I doubt there will be Cordic. They do it standard way, imo.
by Pito
Mon Apr 06, 2020 2:51 pm
Forum: General discussion
Topic: New APM32F103CB
Replies: 44
Views: 7640

Re: New APM32F103CB

That is good.
From my search above the FPU could work with 4 primitives add/sub/mult/div, while add/sub/mult is 1 cycle and div is more cycles (like 14 in F4xx).
The interrupt fires when div finished, imho.
by Pito
Mon Apr 06, 2020 1:59 pm
Forum: General discussion
Topic: New APM32F103CB
Replies: 44
Views: 7640

Re: New APM32F103CB

You need libraries for their FPU usage, otherwise you would be lost..

PS: a search through the SDK shows FPU, with one global FPU interrupt, FPU clock enable flag and FPU_DIV flag.
by Pito
Mon Apr 06, 2020 1:48 pm
Forum: General discussion
Topic: New APM32F103CB
Replies: 44
Views: 7640

Re: New APM32F103CB

In 1.0.2 version of their datasheet they list APM32E103x as the chips with an FPU, in 1.0.5 they list APM32F103x as the chips with an FPU. The above "sc_math_sin asm" does not show the FPU usage at all, you have to dig deeper into asm to find out the actual sine() calculation. The FPU has got most p...
by Pito
Sun Apr 05, 2020 6:47 pm
Forum: General discussion
Topic: New APM32F103CB
Replies: 44
Views: 7640

Re: New APM32F103CB

Here is the (Google) translation for page 14: 3.10. Floating Point Unit (FPU) The product has a built-in independent FPU floating-point arithmetic processing unit, it supports the IEEE754 standard single-precision floating-point arithmetic. As it is memory-mapped on the AHB bus (0x40024000-0x400243...

Go to advanced search