I have to measure distance between an object by ARM1176JZF-S(DS- 5 TOOLS) using ultrasonic sensor. I am not being able to write the codes. I have connected the ultrasonic sensor in the GPIO pins PL061 peripheral bock (j39). Please help me write the codes.
Header file and sample program of ultrasonic distance measuring sensor for mbed is given in HCSR04 - a mercurial repository | mbed and another of ATMega 16 http://www.robokits.co.in/documentation/Ultrasonic%20distance%20sensor.pdf
HCSR04::HCSR04(PinName TrigPin,PinName EchoPin):
pulsedur = pulsetime.read_us();
void HCSR04::rise (void (*fptr)(void))
void HCSR04::fall (void (*fptr)(void))
unsigned int HCSR04::get_dist_cm()
unsigned int HCSR04::get_pulse_us()
Here is a sample code usage
unsigned char count=0;
Sample Program for ATMega16Connections:VCC - +5VDCTrig – PA.6 on ATmega16Echo – PA.7 on ATMega16GND – GNDATMega16 running at 16Mhz
sei(); //Enable global interrupt
sbi(DDRA,6); //Set pin as output
cbi(DDRA,7); //Set pin as input
sbi(PORTA,6); //Send Trigger
cbi(PORTA,6); //Send trigger
http://www.robokitsworld.com Page 4
Ultrasonic Distance Measurement Sensor 4M [RKI-1540]
TCNT0=0; //Clear timer
while(bit_is_clear(PINA,7)); //Wait for rising edge
sbi(TCCR0,CS02); //Select prescalar 256
sbi(TIMSK,TOIE0); //Enable timer0 overflow interrupt
while(bit_is_set(PINA,7) && timer0counter<9) //wait for falling edge of echo
cbi(TCCR0,CS02); //Stop timer
range=(256*timer0counter+TCNT0)*16*0.017; //range conversion
I see that you asked a similar question before on a different part of the community. I'd suggest that if you're definitely going to use ARM11, it might be best to simplify what you are trying to do initially. Try to blink a LED first (so that you know you can control the GPIO from a program running on your board), as ultrasound can be pretty temperamental at the best of times.
The alternative, which might be the fastest way to get this working - would be to get a Raspberry Pi, which is an ARM11 development board providing an easy way to get Linux running, control the GPIO etc. They have a huge community with plenty of people carrying out projects just like yours.
Hope this helps,
In reply to Joe Alderson:
Thank you sir for your suggestion. Because of certain constraints I have to do the project in the versatile realview ARM1176JZF-S. I have worked in mbed, 8051, 8085 processors. I am finding it difficult to start. Please help me start. Rest probably I can manage.
Till now I have been able to debug c programs ( like finding factorilals, fibbonacci, example programs ) in the board through the Dstream debugger. Now please tell me how to begin a program to blink a LED that you suggested. In the eclipse for DS-5 I create a new C project-i name it LED blink- executable--empty project compiler ds 5 GCC toolchain - then add a new source file. In that source file do I need to give header file of this board? If yes , please tell how to get the library of the board. Then how to proceed?
In reply to albert dane:
> If yes , please tell how to get the library of the board.
There isn't one.
As mentioned a few times this board is not designed to be a micro-controller development platform, it's designed to run a big OS like Linux or Android (so the "library" is the Linux OS). There isn't an off-the-shelf bare-metal support library like you get with mbed - it just doesn't exist for this platform. All you really get is the manual I linked in my first post - you're going to have to write much of the library functionality you would find elsewhere yourself.
The manual will give you the address map of all of the peripherals the chip supports, and all of the peripheral manuals will be available separately at http://infocenter.arm.com.
In reply to Peter Harris:
Sir,Please teach me the very basics so that I have an idea to do go ahead. Tell me how to begin a program to blink a LED that was suggested. In the eclipse for DS-5 I create a new C project-i name it LED blink- executable--empty project compiler ds 5 GCC toolchain - then add a new source file.Then how to proceed?
How to boot Linux in this board?
From memory, the CD which came with the board should include some example projects, as should the DS-5 install itself. Try and get one of the examples to compile to an AXF file, and load that via the debugger. It will be easier to get started if you are starting with a "known good" demo which works.
One note on this - the board CD is older than DS-5, so the projects may not work in the IDE without some porting. The DS-5 examples may be built for a board with a different address map, so that may require porting to the board too.
> Tell me how to begin a program to blink a LED that was suggested.
Once you have the demo working program the "LED" part is trivial. Look up the address of the LED control block in the manual. Write a "1" to the relevant bit at that address to turn the LED on, write a "0" bit to turn it off.
If you want to connect a physical LED to the GPIO block on the PCB that may work, but check that voltage the GPIO puts out.
> How to boot Linux in this board?
There _might_ be a Linux build and some instructions on the CD which came with the board, but I'm really not sure. I currently can't find the instructions which I used to use, as the ARM website has moved around quite a lot ...
The only DVD that I have received is the REALVIEW VERSATILE FAMILY PRODUCT SUPPORT DVD which I have installed in my system and the purpose of which I still have not been able to understand (and no where has its purpose been stated) . I am attaching the screenshot containing the support summary, the particular board files and two folders( present within the board files) for your kind perusal. As you can see most of the files are unreadable.
Sir, I am am not being able to control the GPIO pins. I have attached the pages of the user guide containing the GPIO. When I power on the device 18 pins show 3.3 V in multimeter and the rest 16 0 V. How to make some pins 0 and some 1.I have tried many things but did not work including
I am not finding any example program which uses the GPIO pins of the board
You will need to read the manual for the PL061 peripheral itself to work out how to drive the register interface correctly - it is not a simple as just writing to the base address. You're currently just writing to the base address of a multi-register interface, but the address masking functionality of the peripheral means that this doesn't actually write any GPIO lines.
TRM for PL061:
In software mode (i.e. programming through the register interface), bits [9:2] of the address form an 8-bit mask, and only data values which are not masked take effect. In your case:
Bits [9:2] are all zero so nothing takes effect. (FWIW you are missing a * "points to operator, but I assume this is just a typo as the compiler would error otherwise).
I _think_ the code below should clear all the GPIO pins (x3FC = an 8-bit mask of xFF), wait for that to complete, and then set GPIO (x004 = an 8-bit mask of 0x01) to 1.
Note that the data value you write is also an 8-bit on/off mask, not a binary on off for the bit you have selected. If you want to set GPIO to 1 you would need.
I'm not 100% sure this works - I don't have access to one of these boards, so just going by the manual. P.S. you may need to mark up the pointers as volatile, or there is a risk the compiler optimizes them out.
*((volatile unsigned int*)0x1010A008)=2;
Sir, its not working. There is no change in the GPIO pins. I have tried just like you have instructed and also done some other experiments. I , here, provide the screen shots of those.
Try to pick some example projects from the provided code and start with changing few lines of codes and get familiar to it.
In reply to techguyz:
The main problem is that I do not have any example project. I tried some experiments, I am not being able to change/modify the GPIO pins.