LeafLabs Garden » User Favorites: Natalie

LeafLabs Garden » User Favorites: Natalie 4182 A place to share, learn, and grow... en-US Fri, 22 Jan 2016 00:14:31 +0000 http://bbpress.org/?v=1.0.2 <![CDATA[Search]]> q http://forums.leaflabs.com/search.php pmp0x on "Display Shields" http://forums.leaflabs.com/topic.php?id=999#post-12455 Wed, 15 Aug 2012 17:35:48 +0000 pmp0x 12455@http://forums.leaflabs.com/ I try to make it work right now…haven't tested it much but the basic is working…(still lot of nasty Debug and so on… no cleanup at all) you can find it here: <a href="https://github.com/pmp0x/StudienarbeitX" rel="nofollow">https://github.com/pmp0x/StudienarbeitX</a> Check Library/WiFlySerial it's from this side:http://cairohackerspace.blogspot.de/ Anonymous on "Display Shields" http://forums.leaflabs.com/topic.php?id=999#post-12446 Wed, 15 Aug 2012 10:49:31 +0000 Anonymous 12446@http://forums.leaflabs.com/ I am also looking for a way to modify the wiFly lib for Maple. The lib Natalie is refering to must have been updated. Or maybe an older version of the lib was used (if so, wich one?). Anyone has a workaround he can post for everyone to know? robodude666 on "Display Shields" http://forums.leaflabs.com/topic.php?id=999#post-11748 Sun, 15 Jul 2012 11:21:45 +0000 robodude666 11748@http://forums.leaflabs.com/ You should have no issue getting the TouchShield to work. It only uses D2 and D3 for software serial communication. Otherwise, the TouchShield is an Arduino on its own with an LCD and its own IDE. You create the Maple and TouchShield sketches separately. Use serial to communicate between the two. Here's an article on it: <a href="http://iamshadowlord.com/2010/03/touchshield-slide-two-way-communications.html" rel="nofollow">http://iamshadowlord.com/2010/03/touchshield-slide-two-way-communications.html</a> asterix on "Display Shields" http://forums.leaflabs.com/topic.php?id=999#post-11720 Fri, 13 Jul 2012 09:29:14 +0000 asterix 11720@http://forums.leaflabs.com/ I downloaded the library you referenced too however I'm getting far more compile errors than just one. Its also missing quite a few of the files you're referring to (_spi.h, _spi.c etc). Any chance you could send me your working library? Natalie on "Display Shields" http://forums.leaflabs.com/topic.php?id=999#post-7943 Mon, 30 Jan 2012 03:57:03 +0000 Natalie 7943@http://forums.leaflabs.com/ I finally sorted it out ... Note that the following is for the SPI1 port, but can be easily modified to match the SPI2 or SPI3 port if available ... * In "_spi.h", include the "stdint.h" and remove the "pins_arduino.h" * In "_spi.c", include headers "_Spi.h", "libmaple.h", "spi.h", "wirish.h" * In "_spi.c", declare the pins as follow: void SpiDevice::_initPins() { pinMode(BOARD_SPI1_MOSI_PIN, OUTPUT_AF_PP); pinMode(BOARD_SPI1_MISO_PIN, INPUT); pinMode(BOARD_SPI1_SCK_PIN, OUTPUT_AF_PP); pinMode(_selectPin, OUTPUT); deselect(); } * I create the "OUTPUT_AF_PP" case in "wirish_digital.cpp" and "io.h" like this: case OUTPUT_AF_PP: outputMode = GPIO_AF_OUTPUT_PP; pwm = false; break; * In "_spi.c", to initialize (based on spi_init and spi_reconfigure taken from spi.c): void SpiDevice::_initSpi() { rcc_clk_enable(SPI1->clk_id); rcc_reset_dev(SPI1->clk_id); //Disable spi_irq_disable(SPI1, SPI_INTERRUPTS_ALL); spi_peripheral_disable(SPI1); //Mode hardware (to manually drive the NSS pin with the select/deselect functions) //SC16IS750 supports 4 Mbit/s maximum SPI clock speed means this can theoretically handle the SPI_BAUD_PCLK_DIV_32 (2.25 MHz) divider ... //speed = SPI_BAUD_PCLK_DIV_64 = 1.125 MHz //speed = SPI_BAUD_PCLK_DIV_32 = 2.25 MHz //speed = SPI_BAUD_PCLK_DIV_16 = 4.5 MHz SPI1->regs->CR1 = SPI_CR1_SPE | SPI_BAUD_PCLK_DIV_32 | SPI_FRAME_MSB | SPI_DFF_8_BIT | SPI_CR1_MSTR | SPI_MODE_0; SPI1->regs->CR2 = SPI_CR2_SSOE; //enable spi_peripheral_enable(SPI1); //clear registers by reading them int clr = 0; clr = SPI1->regs->SR; clr = SPI1->regs->DR; clr = SPI1->regs->CR1; clr = SPI1->regs->CR2; //flush select(); while((SPI1->regs->SR & SPI_SR_BSY) == SPI_SR_BSY); deselect(); } * In "_spi.c", the transfer function became: byte SpiDevice::transfer(volatile byte data) { // Start the transmission SPI1->regs->DR = data; // Wait for the end of the transmission while((SPI1->regs->SR & SPI_SR_TXE) != SPI_SR_TXE); // Wait for the end of the reception while((SPI1->regs->SR & SPI_SR_RXNE) != SPI_SR_RXNE); // Return the received byte return (SPI1->regs->DR); } * i also had to rename the "ring_buffer" variable in parsedstream because it conflict with a maple variable. * if debugging is activated (i.e ERROR_LEVEL > 0 in debug.h), think about replacing "serial.print" by "SerialUSB.print") poslathian on "Recommand me a lipo battery" http://forums.leaflabs.com/topic.php?id=174#post-7562 Wed, 11 Jan 2012 12:16:03 +0000 poslathian 7562@http://forums.leaflabs.com/ Natalie, I use 2000maH batteries all the time, the kind from sparkfun with the automatic voltage cutoffs. I recommend that style because Maple will continue to draw current even after you fall below the minimum voltage (~2.5V), thus draining your battery all the way to zero if you let it. This is not good for lipos as you know, and recovering from low voltage takes forever as the charger will trickle charge them back up (days). Anyway, the battery charger ostensibly only works with single cell batteries, because it tries to be smart about how it charges them. However, as long as you are using 3.7V (which actually have a nominal full voltage of 4.2) lipos you should be fine. Natalie on "Recommand me a lipo battery" http://forums.leaflabs.com/topic.php?id=174#post-7506 Fri, 06 Jan 2012 04:36:18 +0000 Natalie 7506@http://forums.leaflabs.com/ What is the maximum capacity that can be used with the Maple? For example, is it possible to use a 3.7V 2000mAH LiPo battery? Or is it limited to less than 1000mAH? Does the integrated LiPo battery charger can handle 2000mAH? Natalie on "Display Shields" http://forums.leaflabs.com/topic.php?id=999#post-7189 Fri, 18 Nov 2011 09:31:12 +0000 Natalie 7189@http://forums.leaflabs.com/ Hi, I have a Wifly Shield, based on RN131, connected to a Maple board. I download the corresponding library from <a href="https://github.com/sparkfun/WiFly-Shield" rel="nofollow">https://github.com/sparkfun/WiFly-Shield</a> But it fails compiling the WiFly library because there is no "pins_arduino.h" file. What is the corresponding header file for the Maple? <a href="http://leaflabs.com/docs/arduino-compatibility.html" rel="nofollow">http://leaflabs.com/docs/arduino-compatibility.html</a> says the Wifi Shield is compatible. Does anyone managed to run a Maple with Wifly Shield? gbulmer on "Tuning ADC to a specific sample rate (i.e. 8000Hz)" http://forums.leaflabs.com/topic.php?id=849#post-7162 Sat, 12 Nov 2011 20:53:26 +0000 gbulmer 7162@http://forums.leaflabs.com/ hbdgas - there is an ongoing development of SD access using DMA by polpla, see: <a href="http://forums.leaflabs.com/topic.php?id=112&page=5#post-6711" rel="nofollow">http://forums.leaflabs.com/topic.php?id=112&page=5#post-6711</a> Edit: oops you already have :-) hbdgas on "Tuning ADC to a specific sample rate (i.e. 8000Hz)" http://forums.leaflabs.com/topic.php?id=849#post-7160 Sat, 12 Nov 2011 19:34:33 +0000 hbdgas 7160@http://forums.leaflabs.com/ gbulmer, Thank you for the quick response. I think I will try the external trigger. One more question, admittedly I am not a great programmer, and I was planning on using the SDFat library to do the SD writes. I do not think the library supports DMA at this time(I could be wrong). How hard is it to write to SD using DMA? gbulmer on "Tuning ADC to a specific sample rate (i.e. 8000Hz)" http://forums.leaflabs.com/topic.php?id=849#post-7156 Sat, 12 Nov 2011 16:22:35 +0000 gbulmer 7156@http://forums.leaflabs.com/ hbdgas - it is relatively straightforward to slow anything down by using a busy loop. If you want roughly a 16KHz sample rate, you could do something like: <pre><code>const unsigned usecs_duration = 1000000/16000; // actually 62.5 usec, but this is integer division //... loop() { // ... unsigned now = micros(); int val = analogueRead(pin); while ((micros()-usecs_duration) < now) ; /* do nothing */ //... }</code></pre> This won't be very accurate though, because the amount of time is actually 62.5 usec (so almost 1% error), the micros() function doesn't take the same amount of time every time it is called, and there are concurrent interrupts stealing time. So a better approach would be to trigger the ADC conversion with a timer. This is described in the manual RM0008 (from ST Micro) in section 11.7 "Conversion on external trigger". You could save the converted values to RAM with DMA, and move it to SD using DMA. <blockquote> The desired sampling rate is 16kHz, but I read earlier in this topic that the slowest sample time for the adc is equivalent to 50kHz. </blockquote> As you will have read in post <a href="http://forums.leaflabs.com/topic.php?id=849#post-5140" rel="nofollow">http://forums.leaflabs.com/topic.php?id=849#post-5140</a> this adjustable sample time is primarily intended to ensure the electronics of the ADC gets an accurate sample of the input voltage. It is not really intended to be used to adjust the ADC to a specific sample rate, it is a bit too crude for that. Using this mechanism in this case would have the effect of blocking a program inside the <code>analogRead()</code> function, unless you implemented that yourself. Blocking inside <code>analogRead()</code> would just waste time that you might need to do some processing (though it is no more wasteful that the busy loop I wrote here). (full disclosure: I am not a member of LeafLabs staff.) hbdgas on "Tuning ADC to a specific sample rate (i.e. 8000Hz)" http://forums.leaflabs.com/topic.php?id=849#post-7154 Sat, 12 Nov 2011 15:10:45 +0000 hbdgas 7154@http://forums.leaflabs.com/ Hi, I'm currently working on a school project that involves sampling audio data from a microphone and saving the data to a SD card. In order to give the CPU as much time as possible to write to the SD card, I'm considering using DMA. The desired sampling rate is 16kHz, but I read earlier in this topic that the slowest sample time for the adc is equivalent to 50kHz. Does anyone have any suggestions on how to slow the sampling rate further? gbulmer on "Tuning ADC to a specific sample rate (i.e. 8000Hz)" http://forums.leaflabs.com/topic.php?id=849#post-6232 Thu, 08 Sep 2011 20:36:30 +0000 gbulmer 6232@http://forums.leaflabs.com/ robodude666 - dump all the TIMER3 registers. There must be something different. I calculate as follows: <code>uint32_t cycles = (uint32_t)(22.671f * (float)CYCLES_PER_MICROSECOND);</code> is 22.671 * 72 -> cycles is 1632 <code>uint16_t pre = (uint16_t)((cycles >> 16) + 1);</code> 1632 >> 16 = 0, so pre is 1 so <code>timer_set_prescaler(TIMER3, pre);</code> is <code>timer_set_prescaler(TIMER3, 1);</code> and <code>Timer3.setPrescaleFactor(pre);</code> is <code>Timer3.setPrescaleFactor(1);</code> In which case mbolivar's point would explain it. In one case the precscaler divides the clock by 1, and in the other, by 2. If you dump TIM3_PSC in both cases, it should be clear. (if that isn't the explanation, dump all the registers :-) mbolivar on "Tuning ADC to a specific sample rate (i.e. 8000Hz)" http://forums.leaflabs.com/topic.php?id=849#post-6219 Thu, 08 Sep 2011 02:57:10 +0000 mbolivar 6219@http://forums.leaflabs.com/ <blockquote> With the same pre and cycles values as calculated above </blockquote> Careful! timer.h uses prescaler values appropriate for writing to the PSC registers (i.e., 0-based). HardwareTimer uses 1-based prescalers. Are you sure you're not off by one? robodude666 on "Tuning ADC to a specific sample rate (i.e. 8000Hz)" http://forums.leaflabs.com/topic.php?id=849#post-6199 Tue, 06 Sep 2011 11:59:50 +0000 robodude666 6199@http://forums.leaflabs.com/ Sorry for the late response. I printed out the CR1 register using: <pre><code>Serial2.print("CR1: "); Serial2.println((TIMER3->regs).bas->CR1, HEX);</code></pre> and in both cases the CR1 register is set to 0x81. This configures the timer to be in up-count mode using edge-alignment.