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by Z3r0
Mon Nov 26, 2012 8:29 am
Forum: General discussion
Topic: New IT (UK) Supplier
Replies: 178
Views: 29240

Re: New IT (UK) Supplier

So i am another happy customer of newIT :) A little bit of back story: i ordered my pi at RS on June 26, it was dispatched October 4 and on November 12 i got a refund, because i never received it.... What a waste of time. But then i found about newIT guys/gals :) saw that they have in stock, ordered...
by Z3r0
Sat Sep 22, 2012 9:14 am
Forum: Bare metal, Assembly language
Topic: Using GPIO Clocks
Replies: 10
Views: 17103

Re: Using GPIO Clocks

When i was playing with gpio clocks i was able to get it working only with oscillator source, none of PLL was working for me (1 = oscillator) also test first without any dividers, i was able to get only around 2Mhz in my early tests from gpio clock with oscillator source. also look into https://gith...
by Z3r0
Mon Sep 10, 2012 8:01 pm
Forum: Bare metal, Assembly language
Topic: Baking Pi
Replies: 168
Views: 30144

Re: Baking Pi

Most likely from error your are on 64bit linux and missing 32 bit libraries, package ia32-libs if i am not mistaking.

uu sorry mac, didn't catch that, still the problem can be same, just don't know what to install on mac :)
by Z3r0
Mon Sep 10, 2012 7:49 pm
Forum: Bare metal, Assembly language
Topic: Clock speeds in bare metal?
Replies: 16
Views: 6592

Re: Clock speeds in bare metal?

So it seems we have now control over clocks (as it seems firmware update with that was 5 days ago) Just tried to push pwm clock http://zero.hotbox.lt/RPi/100.png Postmam message says pwm clocks max frequency could be 500Mhz, sad but my oscilloscope goes only to 100 :) and probes will not handle more...
by Z3r0
Mon Sep 10, 2012 6:35 pm
Forum: Bare metal, Assembly language
Topic: Baking pi objdump failing on Windows
Replies: 3
Views: 1714

Re: Baking pi objdump failing on Windows

it works for me with no problem win 7 x64 did you restart your pc after installing yagarto?
(I tried without rebooting thinking why should i, and it failed, just don't remember which tool)
by Z3r0
Mon Sep 10, 2012 6:29 pm
Forum: Bare metal, Assembly language
Topic: Clock speeds in bare metal?
Replies: 16
Views: 6592

Re: Clock speeds in bare metal?

I used a spring connector so well ~3cm. The probe it self is not high quality, but still i was able to get >50mhz squares in good quality with it :)
by Z3r0
Mon Sep 10, 2012 4:58 pm
Forum: Bare metal, Assembly language
Topic: Clock speeds in bare metal?
Replies: 16
Views: 6592

Re: Clock speeds in bare metal?

Ok a little update, in turn on and turn off methods i had additional instructions, checking inputs and so on, when stripped all of that here is the result: CACHE ON single instruction: *(clsReg) = (unsigned int)(1 << 14); http://zero.hotbox.lt/RPi/cache_on_single.png CACHE OFF single instruction: ht...
by Z3r0
Mon Sep 10, 2012 4:22 pm
Forum: Bare metal, Assembly language
Topic: Clock speeds in bare metal?
Replies: 16
Views: 6592

Re: Clock speeds in bare metal?

So i hooked an oscilloscope and tried to turn on the cache, results: Cache OFF: http://zero.hotbox.lt/RPi/cache_off.png Cache ON: http://zero.hotbox.lt/RPi/cache_on.png As you can see improvement is double the speed ~2Mhz still my simple atmega8 can output more :) I also found https://github.com/ras...
by Z3r0
Mon Sep 10, 2012 6:51 am
Forum: Bare metal, Assembly language
Topic: Flashing the LED 5 times.
Replies: 23
Views: 5484

Re: Flashing the LED 5 times.

Good to hear that it helped :) Its no need to jump out to another empty loop. In first example yes it was able to overflow and restart r4 from 0, but its not so easy to increment a 32bit register (it would take few seconds) so it would be a gap between each 5 flashes. And then Jamie modified his cod...
by Z3r0
Mon Sep 10, 2012 5:28 am
Forum: Bare metal, Assembly language
Topic: Clock speeds in bare metal?
Replies: 16
Views: 6592

Re: Clock speeds in bare metal?

Thx everyone for the help, will try this as soon as i come back from work. Pwm and gpio clocks are hardware, so i guess its a different story, unless we get info on clock manager i guess. But at lest pin switching will improve :) if pcb is able to carry high frequency i guess :) thx for your help
by Z3r0
Sun Sep 09, 2012 8:50 pm
Forum: Bare metal, Assembly language
Topic: Raspberry Pi OS
Replies: 82
Views: 19055

Re: Raspberry Pi OS

Os boots, looks nice :) but keybord dont work. Oldie logitech deluxe 250
by Z3r0
Sun Sep 09, 2012 6:16 pm
Forum: Bare metal, Assembly language
Topic: Flashing the LED 5 times.
Replies: 23
Views: 5484

Re: Flashing the LED 5 times.

I think i got this. In BlinkLed you dont cach lr coming frok your loop (push/pop) that means when you call something inside blinkled you lr to previuos loop is lost, and it never returs to that loop. Insted of mov pc, lr in blinkled do: push{lr} before any bl ant at the end pop{pc}
by Z3r0
Sun Sep 09, 2012 6:10 pm
Forum: Bare metal, Assembly language
Topic: Clock speeds in bare metal?
Replies: 16
Views: 6592

Re: Clock speeds in bare metal?

Probably not, i am quite a bigginer in low level arm. Will search info on that, thx
by Z3r0
Sun Sep 09, 2012 11:17 am
Forum: Bare metal, Assembly language
Topic: Clock speeds in bare metal?
Replies: 16
Views: 6592

Clock speeds in bare metal?

I was playing a bit with c/asm in low level (without linux). Tried the maximum switching speed for pins: turning pin on and of via registers was only around: 1Mhz using gpio clock using int divide (no MASH) max 1Mhz using pwm (with limited info on clock manager) clock divider of 2 max 5Mhz Its a bit...
by Z3r0
Sat Sep 08, 2012 9:40 pm
Forum: Bare metal, Assembly language
Topic: Flashing the LED 5 times.
Replies: 23
Views: 5484

Re: Flashing the LED 5 times.

are you returning from BlinkLED label?. And what actually is the problem, does the led blink without stooping or just blinks once?
by Z3r0
Sat Sep 08, 2012 6:47 pm
Forum: Bare metal, Assembly language
Topic: Simple question regarding register addresses
Replies: 4
Views: 1775

Re: Simple question regarding register addresses

Yeah but its explained in the beginning. And still another problem rises with registers. Now when i read about PWM i only find "PWM Address Map" thats ok but where's the base address? For every other registers i saw a base address, but not for pwm controll.
by Z3r0
Sat Sep 08, 2012 3:42 pm
Forum: Bare metal, Assembly language
Topic: Simple question regarding register addresses
Replies: 4
Views: 1775

Re: Simple question regarding register addresses

feeling so dumb now :D i always miss some important part from the specifications..
Thank you for making things clear!
by Z3r0
Sat Sep 08, 2012 3:26 pm
Forum: Bare metal, Assembly language
Topic: Simple question regarding register addresses
Replies: 4
Views: 1775

Simple question regarding register addresses

So i have a small question.
Now in BCM2835 ARM peripherals datasheet, for example GPFSELn
starts at 0x7E200000 but everyone in their code uses 0x20200000. Now can someone explain why the address shifts down and are the offset constant to all register addresses not only gpio.

Thank you
by Z3r0
Sat Sep 08, 2012 8:59 am
Forum: Advanced users
Topic: Raspberry Pi as a Warflying tool
Replies: 4
Views: 2220

Re: Raspberry Pi as a Warflying tool

Why external power? just use the lipo on your rc. If your's bec is 5 volts, then no modification needed. If more just hook an dc to dc converter with few caps.
by Z3r0
Fri Sep 07, 2012 9:23 pm
Forum: Advanced users
Topic: overclocking disasters?
Replies: 4
Views: 1639

Re: overclocking disasters?

You will not brake the pi with overclocking, it can become unstable a bit more heat but not brake. Overvolting on the other hand is very different story. Sure pi my work as good as new, but there are few things. First the first time you try overvolting flag in chip is set and your warranty becomes v...
by Z3r0
Wed Sep 05, 2012 8:50 pm
Forum: Bare metal, Assembly language
Topic: Baking Pi screen01
Replies: 49
Views: 11015

Re: Baking Pi screen01

Seems can't edit posts, so sorry for double post. In any case i made some test, and saw that i add drawing.s from any later examples to my project, it then works without replug, even if i don;t use anything from drawing.s. So i tried to rename drawing.s to some zdrawing.s (that linker would join it ...
by Z3r0
Wed Sep 05, 2012 8:12 pm
Forum: Bare metal, Assembly language
Topic: Baking Pi screen01
Replies: 49
Views: 11015

Re: Baking Pi screen01

In your text it says 4 but code uses 12 :) the funny thing is i just tried (after writing the question) Piscreen04 from downloads and it worked without need of replug. Need to check the diference. Maybe i wrote 4 but thinking about 12. By the way, thx for the tut its awesome! :)
by Z3r0
Wed Sep 05, 2012 7:49 pm
Forum: Bare metal, Assembly language
Topic: Baking Pi screen01
Replies: 49
Views: 11015

Re: Baking Pi screen01

I also have a question regarding this lesson. Everything is fine but, the problem is that i as well need to unplug and plug back hdmi connector to get the buffer address from vcore. So maybe there are some one who actually can help on this problem (i am afraid that in multiple reconnects hdmi port c...

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