Jump to content


  • Content Count

  • Joined

  • Last visited

Reputation Activity

  1. Like
    32614_1489253935 got a reaction from exemaspilasem in New Book: Programming the BeagleBone Black   
    Hi Si,
    I'm using Ubuntu 13.04 on BBB, I have found many way to install Cloud9 IDE but currently i can not use bonescript when i access to as many tutorial on Angstrom.
    if you have done with my problem, plz give me solution.
    Much appreciated!
  2. Like
    32614_1489253935 reacted to Lyon in can not debug   
    First of all, your JTAG pins must have a pull-up resistors mounted on-board.
    Second, if you use your Lauchpad board as debug-out ( to debug another board) then you must disable your LP target micro ( the test/target micro from LP board, the debug one should be active). You can do that by short-circuit of reset capacitor on LP board.
  3. Like
    32614_1489253935 reacted to L.R.A in encoder interface   
    As i said, the TM4C123G launchpad tolerates 5V input voltages.
    If you still need to convert:
    Just use a voltage divider https://www.abelectronics.co.uk/docs/tools/resistor/voltage-divider.gif
    It's simple. Just remember to take current into account, not to little nor too much. This basically turns a scale of 0V-5V to a scale 0V-3.3V
    Other way for digital signals is this one: http://repetae.net/zenerresistor.png
    You could always use 1 mosfet per data line, but that should not be necessary, since it's not a bi-directional signal. http://i.stack.imgur.com/64Dk9.png  
    You can read this too http://www.ti.com/lit/an/slaa148/slaa148.pdf  
    All of this can easily be found in google images by just typing "5V to 3.3V"
    The encoder outputs a PWM signal. Just that. You should not have problems with any of the methods if applied correctly. Ex: if the enconder outputs a high frequency you can't use resistors to big like 1M which would mean a really low current, but try to keep about 2mA max input into you MCU pins
  4. Like
    32614_1489253935 reacted to L.R.A in encoder interface   
    I don't think a schmitt trigger is that much necessary for this case, i usually use that just for buttons.
    As for converting 5V to 3.3V, the easiest way is use a voltage divider with 2 resistors. Though the encoder output should be digital, and the TM4C123GH6PM is 5V tolerant in most pins, in that case it's not necessary the conversion
  5. Like
    32614_1489253935 reacted to Lyon in using ADC tivalaunchpad   
    At the motobike battery voltage, the ADC offset mostly does not matter, or is within a good accuracy. It can be measured and used into a formula to get better results, but at the expense of some external components. More, you must scale down the voltage to be within the ADC range, (the maximum scaled battery voltage should be less than maximum ADC range) and the scaling is better to be done with resistors and an op-amp, since the ADC input impedance is not so high.
    TI has all sort of components to make measurements, including temperature sensors. Choose whatever is convenient to you. I prefer ones giving scaled results (degC/mV inmy case) since I only measure the voltage without too much calculations.
  6. Like
    32614_1489253935 reacted to spirilis in Compare TM4C123GH6PM and TM4C1233H6PMI   
    ti.com/tiva - product brochure:
    Looks like the TM4C1233 only has 1 CAN, only USB Device (no OTG), no PWM outputs (so just like the original Stellaris LaunchPad's MCU in that regard).... and I believe that sums it up.
  7. Like
    32614_1489253935 reacted to Lyon in make a circuit with H6PM sample   
    First this one: http://www.ti.com/lit/an/spma059/spma059.pdf
    The second, Launchpad board manual, hope you have it.
    One word of caution: you say:
    "can use all function as a Tiva Launchpad without JTAG."
    but design the board with JTAG connector, otherwise you are lost...
  8. Like
    32614_1489253935 reacted to Lyon in SSI trouble   
    This is related to Digital Function selection (GPIOPCTL PMCx Bit Field Encoding)- see page 648/Table10-2 (GPIO Pins and Alternate Functions). It is the value to be written into PMCx, x=0..7, corresponding to the pin. L
  9. Like
    32614_1489253935 reacted to Lyon in SSI trouble   
    Unfortunately you forgot to attach the file...
  10. Like
    32614_1489253935 reacted to Fred in Step motor trouble   
    I'm not sure you've quite got the concepts of driving a stepper. (You might have, but without seeing the code I can't be sure.) By far the easiest way to drive a stepper is to use a stepper motor driver. A common example is Pololu's A4988 board. You drive this by setting the direction and sending a pulse to the step pin to make it move one step. I've had a Tiva Launchpad driving some of these without a problem. I could probably dig out some sample code if needed.
  11. Like
    32614_1489253935 reacted to Kartman in WTIMER0 and TIMER0   
    From what i can recall, you have a 32bit timer or two 16 bit timers A and B. So, i would say the answer is no.
  12. Like
    32614_1489253935 reacted to igor in WTIMER0 and TIMER0   
    Yes, you can use them simultaneously.  The timers are separate devices.
    As Kartman notes you can split either or both timers  - WTIMER0A and WTIMER0B are both 32 bit timers.
    TIMER0 is a 32 bit timer, or TIMER0A and TIMER0B are 16 bit timers.
  13. Like
    32614_1489253935 reacted to abecedarian in WTIMER0 and TIMER0   
    Starting on page 704, gives details regarding the timers and which pins can be used for the various configurations.
  14. Like
    32614_1489253935 reacted to Lyon in WTIMER0 and TIMER0   
    Wtimer is a 64 bit timer, while the usual Timer is only 32 bit timer.
    Now: you ca split a timer in two halfs, but those have a capacity half of the "name": for a WTimer, WTimer0A is 32 bits wide, while for usual Timer, Timer0A is 16 bits wide. Similar for WTimer0B vs. Timer0B.
  15. Like
    32614_1489253935 reacted to abecedarian in WTIMER0 and TIMER0   

    TIMERA: = 32 bits wide TIMERB = 32 bits wide | ---------- TIMERA ---------- | | ---------- TIMERB ---------- | 00000000000000000000000000000000 00000000000000000000000000000000 WTIMERx = 64 bits wide equals TIMERA + TIMERB 00000000000000000000000000000000 00000000000000000000000000000000 | --------- WTIMERxA ----------| | --------- WTIMERxB ----------| TIMERx: = 32 bits wide TIMERx+1 = 32 bits wide 00000000000000000000000000000000 00000000000000000000000000000000 | -- TIMERxA --||-- TIMERxB -- | | - TIMERx+1A -||- TIMERx+1B - |I probably messed that up, but I think it's correct.
  16. Like
    32614_1489253935 reacted to igor in WTIMER0 and TIMER0   
    It may be confusing that getting sometimes conflicting answers here.
    I hope that the pointers to the documentation help.
    Of course trying it out for yourself is the real way to be sure.  Unfortunately the only example code that I know of off the top of my head is parts of fairly large projects.
    Looking in the source code to Energia if you look in hardware/lm4f/variants/stellarpad/pins_energia.h
    in the digital pin to timer array you will see that some pins are mapped to wide timers (WTxx) and some to regular timers (Txx)
    then in the cores/lm4f directory you can look at the source to wiring_analog.c - and see how it is using the respective timers to do PWM.
    To prove that they operate independently do a quick sketch that uses PWM on a pin that is controlled by WT0A and a different PWM on a pin controlled by T0A (for instance).
    You will find that you can control them independently.
  17. Like
    32614_1489253935 reacted to igor in WTIMER0 and TIMER0   
    Yes they are separate timers.  Yes you can use them simultaneously.
    WTIMER0 is a separate device from TIMER0 (and from any part of timer 0, i.e. TIMER0A/TIMER0B), they do not overlap, you can use them simultaneously and independently.
    WTIMER0A and WTIMER0B are parts of WTIMER0 (i.e. can't use WTIMER0 and WTIMER0A independently at same time).
    TIMER0A and TIMER0B are parts of TIMER0 (can't use TIMER0 and TIMER0A independently at same time)
    But you can use parts of WTIMER0 and parts of TIMER0 at the same time, independently.
    (i.e. WTIMER0A does not overlap with TIMER0A, etc.)
    The decision whether to split a timer or use it total is on a per timer basis (i.e. can use TIMER0 unsplit, but use WTIMER0A and WTIMER0B, etc.)
    See TM4C123gh6pm datasheet - chapter 11, for instance look at the register map (11.5) 
    Note that the 16/32 bit timer devices have separate addresses from the 32/64 bit devices. (i.e. they have separate control registers)
    Note that the pins the various timers can control are different, etc.
  18. Like
    32614_1489253935 reacted to L.R.A in SysCtlClockget, Drive Strength   
    If you don't need much drive strength just use 2mA. Normaly it's enough. Only at high switching speeds more is needed
  19. Like
    32614_1489253935 reacted to igor in SysCtlClockget, Drive Strength   
    SysCtlClockGet has an error in Tivaware version so it does not read correctly if you set the clock to 80MHz.
    (I don't remember if other frequencies are affected.)  Not sure in which version of the library this error was introduced, or whether it has been fixed.
    One workaround is to remember what clock speed you set the processor to.
    Edit: This message has a little more detail and links to how to patch Tivaware:
    (Also be aware that this call is not available on the TM4C1294).
  20. Like
    32614_1489253935 got a reaction from exemaspilasem in List webcam for Beaglebone Black   
    Hi everyone,
    Can i see the list of webcam which actually active on ubuntu ?
  21. Like
    32614_1489253935 got a reaction from exemaspilasem in Error when install compiler for PRU   
    Here is my fault, plz give a solution, thanks Dear!
    Make... has modification time in the future

  22. Like
    32614_1489253935 reacted to bluehash in Offset DTO   
    Look at Table 9-57. conf_<module>_<pin> Register Field Descriptions of the AM335x Technical Reference Manual for the bitfields:

  23. Like
    32614_1489253935 reacted to L.R.A in ADC0-ADC1 PERIPL   
    well you see how you have PA1, PA2, PB1?
    the leter A,B or any other specifies the GPIO module. There's a peripheral, a component inside the chip that drives the digital ports. Each one having 8 (therefore the Px0 to Px7).
    With the ADC it's the same. There's 2 modules. Each one with a number of ADC input chanels. Simple answer, you use one of them everytime you need to read a analog input.
    For the older tiva launchpad, the one with the TM4C123GH6PM, the input chanels are shared, meaning the 12 ADC inputs can be read from any of the 2 ADC. How is this useful? Well if you want to read 2 inputs at the same time with an ADC? you can't! you can read them with uS diference or less, but there can't be readings at the same time. But you have 2 ADC, meaning you can read 2 inputs at the same time.
    Also this alows to not having to set up interrupts, triggers, sample rates, etc, etc each time you want to read a diferent analog pin.
    You have a critical reading that needs that config and is being read all the time? well, keep those configs and use the other ADC.
  24. Like
    32614_1489253935 got a reaction from exemaspilasem in I2CwithDS1307   
    Hi guys,
    I use DS1307 connect SDA,SCL to pin I2C2 of BBB, provide power for DS1307, I access to /dev but i can't find 'rtc1', it only have 'rtc0' as  a default. I have use command to append address then using 'i2cdetect....' but no more effect.
    Hope you can help me!

  25. Like
    32614_1489253935 got a reaction from exemaspilasem in How can i use uart to exchange data other microcontroller   
    I have beaglebone black install ubuntu 13.04, i wanna send a data to LM4F120XL and receive data from it, have anyone used to do it? plz give a suggest or a tutorial ?
  • Create New...