http://www.8051projects.net/ Learn to make simple microcontroller projects, pic, 8051, avr and arm projects. download 8051 projects, tutorials, libraries, sample codes. join the microcontroller discussion forum and ask doubts regarding electronics. the best source for 8051 over internet. en-gb 2008-12-02T00:35:26-08:00 contact@nospam.com hourly 1 2000-01-01T12:00+00:00 http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 sir , i am using seven segment display for my project, actually i am not much familiar with the seven-segment-display,i just want to know its configuration,now it operates,i hv to connect this 7-segment display to port1 of mymicrocontroller .i am designing the circuit on a breadboard,so please helpmehow toconnect this 7-segment display as i am verynew to it. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V the pin/segment configuration is same for both SP5501 and SP5503 but the difference is in Pin 3 & 8, they connect to Ground in SP5503 and to V+ in SP5501My advice is to separate the ADC and Display to two ports, use ADC on port 3 and Display on port 1 or any free 8 bit port, do this first and make changes in the code Arun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir,in the last post i asked u a very silly question,actually i was not able to express my doubt properly,by connection procedure i wanted to mean the pin configuration of the chip SP5503. I know its a commom cathode chip,so i have changed my programming also. i am trying a lot to find its pin configuration,but i am unable to do so.so,please give me the pin configuration of this chip.please send a quick reply, thanking u, http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 thanx sir,i'll try 2 correct my connection.sir,i have tried 2 correct my program codeiam enclosing it once more,the problem is that when i simulate my program at port p1 it only shows 2 digits 3f and 06.if i add the instruction MOV P1,#00h after every displayin order to clear the displays ,when i connect my circuit 7-segment only displays 8 and 0.please sir help me out of this problemsetb p2.5setb p2.6intr bit p2.7setb intradc_port equ p1adc_val equ 30hvoltage_val equ r3org 0hstart: acall read acall conversion mov a,adc_val sjmp startconversion: clr wr setb wrread: clr rd mov a,adc_val setb rd mov r3,#00h mov a,#00h cjne a,#00,over1 over1: acall data_display1 mov r3,#01h mov a,#33h cjne a,#51,over2 over2: acall data_display2 mov r3,#02h; mov a,#67h; cjne a,#103,over3 over3: acall data_display3 mov r3,#03h mov a,#97h cjne a,#151,over4 over4: acall data_display4 mov r3,#04h mov a,#99h cjne a,#153,over5 over5: acall data_display5 mov r3,#05h mov a,#0ffh cjne a,#255,over6 over6: acall data_display6 data_display1: mov a,#00h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_sevensegment acall delay mov a,r6 acall disp_sevensegment acall delay mov a,r5 acall disp_sevensegment acall delay ret data_display2: mov a,#33h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_sevensegment acall delay mov a,r6 acall disp_sevensegment acall delay mov a,r5 acall disp_sevensegment acall delay ret data_display3: mov a,#67h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_sevensegment acall delay mov a,r6 acall disp_sevensegment acall delay mov a,r5 acall disp_sevensegment acall delay ret data_display4: mov a,#97h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_sevensegment acall delay mov a,r6 acall disp_sevensegment acall delay mov a,r5 acall disp_sevensegment acall delay ret data_display5: mov a,#99h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_sevensegment acall delay mov a,r6 acall disp_sevensegment acall delay mov a,r5 acall disp_sevensegment acall delay ret data_display6: mov a,#0ffh mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_sevensegment acall delay mov a,r6 acall disp_sevensegment acall delay mov a,r5 acall disp_sevensegment acall delay ret disp_sevensegment: cjne a,#0,d1 mov p1,#03fh acall delay d1: cjne a,#1,d2 mov p1,#06h d2: cjne a,#2,d3 mov p1,#05bh d3: cjne a,#3,d4 mov p1,#04fh d4: cjne a,#4,d5 mov p1,#066h d5: cjne a,#5,d6 mov p1,#06dh d6: cjne a,#6,d7 mov p1,#7dh d7: cjne a,#7,d8 mov p1,#07h d8: cjne a,#8,d9 mov p1,#07fh d9: cjne a,#9,d10 d10: mov p1,#067h delay: mov r4,#200 here: djnz r4,here ret end it has been a very lengthy post,please sir excuse me for this. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V hello priya 123,use this forum for help when your preliminary search doesn't give you good results.before posting your queries try googling, don't expect spoon feeding here. below are the results for what you asked next time such queries will be deleted without explanation.Arun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 abbas1707 http://www.iguanalabs.com/7segment.htmhttp://esd.cs.ucr.edu/labs/dec_counter/dec_counter.html http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Shailesh NAYAK Hi,Please ensure your seven segment display is common cathode or common anodesince Seven segment display is nothing but bunch of LED's, which are available in either common anode or common cathode.http://www.hobbyprojects.com/the_diode/seven_segment_display.html http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 pdi33 priya,please mention the part no. of ur LED display that u are going to use so that we can determine the connection ciruit required by u. listed below are sone part no.s and description:LT542 : common anode single digit display (0.56") LT543 : common cathode single digit display (0.56") HP5501 : common anode single digit display (0.53") HP5503 : common cathode single digit display (0.53")KLS51 : common anode single digit display (0.5") the alphabets may change depending upon the manufacturer e.g. LT542 is from Liton and VT542 is from visiontek.In addition, u also get an internally multiplexed 2/3/4 digit displays where the segments are internally connected and u get the shorted eight segment pins and the common anode/cathode of each digit. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir, the part number of my LED(7 segment display) is SP5503. please provide me the details of this chip and its connection procedure. thanking u. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V Hello priya123,i am Shocked to find that you are writing program to connect 7-seg display without knowing how to test a 7-seg display ? use some elementary tools like "multimeter" to find the type of display.SP5503 - is a common cathode display which you should avoid in this projectSP5501 - is a common anode display which you should use here.most of the single 7 seg- displays have 10 pins (5 up /5 down or 5 Left side or 5 right side) pin 3 and pin 8 are common ( to be connected to GND or V+ depending on the type).on your Digital multimeter select the Diode test range and connect the red probe (+) of your meter to pin 3 or pin 8 and connect black (-) probe to other pins one by one - check if the segments glow -if it glows then you have a Common anode typenow connect black probe to pin 3 or pin 8 and touch the red probe to other pins, if the segs glow then you have a Common cathode type.I feel embarrased to tell you these primitive thingsThese are the basics you should have known when you have reached this farnext you might ask how to test a Transistor ?Arun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 pdi33 check this link. it will provide u detailed pin description of various LED displays.http://www.kwalityindia.com/main.htmlthe display u are using is the 0.5" common cathode display (KLS5XX equivalent of kwality phototronics.).u will also get more info from that site. Try to understand the principle first before going ahead.Good Luck. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 for my project as i am using common cathode 7-segment display,i have sent these values .please tell me whether these are the correct valueshex no . 7-segment equivalent0 --------------------- 3f1 ------------------------ 062 -------------------------- 5b3 ----------------------------- 4f4 ------------------------------------ 665 ------------------------------------- 6d6 --------------------------------------- 7d7 ----------------------------- 078 -------------------------------- 7f9 ---------------------------------- 67 http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 pdi33 hi priya, seems u have not read my previous post carefully. I have given a link to a page which contains the pin description of the LED displays.Just check the pin description of KLS5XX series which is same as ur SP5503. here is the link againhttp://www.kwalityindia.com/main.htmlregarding the hex values, well it totally depend upon how u are connecting the individual segments to the port pins like say segment a to port 0.0, segment b to port0.1...etc. U will have to give us that data as well for us to verify if ur hex table is correct. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir,i have gone through the description of the chip KLS5XX.i have connected the following port pins of my microcontroller(8051) with the following segments of my seven-segment-display(KLS5XX). PORT PIN NO(8051): SEVEN SEGMENT DISPLAY (SP5503) P3.0-------------------------------------------------------------------A (PIN NO 7) P3.1-------------------------------------------------------------------B (PIN NO 6) P3.2--------------------------------------------------------------------C (PIN NO 4) P3.3--------------------------------------------------------------------- D (PIN NO 2) P3.4--------------------------------------------------------------------- E(PIN NO 1) P3.5--------------------------------------------------------------------F (PIN NO 9) P3.6--------------------------------------------------------------------G (PIN NO 10) P3.7--------------------------------------------------------------------DP (PIN NO 5) As the chip i am using is a common cathode configuration so at the common pin(PIN NO 3)i have provided a 330 ohmresistor and grounded it. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V Hello Priya,there are few things you need to know :1) Micros like 8051 are good at sinking Current than sourcing current (2 mA); so its better to use Common Anode type rather than c.cathode, still if you want to use C.cathode type then the display will turn on very dim ( if directly connected to port pins - which you are doing right now)2) the hex values for each number are correct with respect to Common cathode display - but your assembler/compiler may show error "undefined symbol" for those hex values- so you have to Use them in Binary form for eg: for displaying Number 9, instead of 67H use 01100111b in your program.3) there is one more problem with Common cathode type - at the time of power on since all the ports are inputs i,e logic 1's your display will show '8." so the first instruction in your main program should be MOV P1,#00H 4) Use non inverting octal Buffer like 74HC244 - between Port pins and the display for more current 5) use of single Common Resistor is wrong, when more segments are "ON" the display looks feeble, when number like "1" is displayed it looks bright- so use independent resistors for each segment so that the segment LEDs don't have to fight for Current shareAll the best Arun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir, i have connected the entire circuit on the breadboard.i have used separate resistors for every display,but when i turn on my circuit the 7-segment display lights up and shows 8.display is bright but after that only segment g is lighted and it shows no further results, but the logic of my program is that whenever i vary the voltage say when i place it at 1volt it should show 33.first it should display3 and again 3.in between these 2 displays there is some delay.my program logic is: for 1volts i want the display to be 33h,for 2 volts display should be 67h.my circuit is : i have connected an ADC with the microcontroller& then at port1 i have connected this 7-segment display.data lines of ADC are also connected with the port p1 of microcontroller.i am varying the voltage at pin 6 ofADC(0804) i am enclosing my program code.Sir kindly go through this code .please point out what changes are to be made and whether the code is correct or not.please get me out of this problem.my program code is: setb p2.5setb p2.6intr bit p2.7setb intradc_port equ p1adc_val equ 30hvoltage_val equ r3org 0hstart: acall read acall conversion mov a,adc_val sjmp startconversion: clr wr setb wr read: clr rd mov a,adc_val setb rd mov r3,#00hmov a,#00hcjne a,#00,over1over1: acall data_display1 mov r3,#01hmov a,#33hcjne a,#51,over2over2: acall data_display2 mov r3,#02hmov a,#67hcjne a,#103,over3over3: acall data_display3 mov r3,#03hmov a,#97hcjne a,#151,over4over4: acall data_display4 mov r3,#04hmov a,#99hcjne a,#153,over5over5: acall data_display5 mov r3,#05hmov a,#0ffhcjne a,#255,over6over6: acall data_display6 data_display1: mov a,#00h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_7segment acall delay mov a,r6 acall disp_7segment acall delay mov a,r5 acall disp_7segment acall delayret data_display2: mov a,#33h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_7segment acall delay mov a,r6 acall disp_7segment acall delay mov a,r5 acall disp_7segment acall delayret data_display3: mov a,#67h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_7segment acall delay mov a,r6 acall disp_7segment acall delay mov a,r5 acall disp_7segment acall delayret data_display4: mov a,#99h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_7segment acall delay mov a,r6 acall disp_7segment acall delay mov a,r5 acall disp_7segment acall delayret data_display5: mov a,#97h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_7segment mov a,r6 acall disp_7segment mov a,r5 acall disp_7segment acall delayret data_display6: mov a,#0ffh mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov a,r7 acall disp_7segment mov a,r6 acall disp_7segment mov a,r5 acall disp_7segment acall delayret disp_7segment: mov p1,#00h cjne a,#0,d1 mov p1,#03fh d1: cjne a,#1,d2 mov p1,#06h d2: cjne a,#2,d3 mov p1,#5bh d3: cjne a,#3,d4 mov p1,#04fh d4: cjne a,#4,d5 mov p1,#066h d5: cjne a,#5,d6 mov p1,#6dh d6: cjne a,#6,d7 mov p1,#7dh d7: cjne a,#7,d8 mov p1,#07h d8: cjne a,#8,d9 mov p1,#7fh d9: cjne a,#9,d10 d10: mov p1,#67h delay: mov r4,#200 here: djnz r4,here ret end http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V Are you NUTS ?3) there is one more problem with Common cathode type - at the time of power on since all the ports are inputs i,e logic 1's your display will show '8." so the first instruction in your main program should be MOV P1,#00Hclearly i have mentioned about this problem and solution for that, " MOV P1,#00H"wasn't this supposed to be your first instruction in your code THINK BEFORE YOU INKArun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V i have connected an ADC with the microcontroller& then at port1 i have connected this 7-segment display.data lines of ADC are also connected with the port p1 of microcontroller1) Why in the world did you connect ADC & 7 seg display to the same PORT 1 ? use the ADC on some other free port2) Why do you want to Multiplex data bus lines?3) In which mode are you using AD 0804 - Free running mode or microcontroller master mode ?4) use MOV P1,#00H just after your variables ; the idea is to Blank out the display during power-ups.Arun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir,i know i am disturbing u all too much but i am undone,anyways,u told me to put MOV P1,#00h in my program code,i have put it at the disp_7segment subroutine---is it correct? i have also tried putting the instruction M0V P1,#00H after voltage_val equ r3.when i simulate my program theresults are all the same.after building my circuit the problem which i am facing is the seven-segment display first displays 8 and then after a short while 0 but it further doesnt display any other value when i vary the voltage,i have mentioned my program logic in the earlier posts, i have tried several times but unable to track the problem.sir,please help me to get out of this problem. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 sashijoseph CODE:setb p2.5
setb p2.6
intr bit p2.7
setb intr
adc_port equ p1
adc_val equ 30h
voltage_val equ r3
back: clr wr
setb wr
read: clr rd
mov a,adc_val
setb rd Plenty of mistakes in this ADC code.What is 'rd' ,'wr'...? Where are you reading the ADC value from adc_port?First thing go through this... http://www.8051projects.net/adc-interfacing/adc0804-8051-programming.phpand correct your adc routine.What Vref/2 value have you chosen?You have 'hardcoded' your display routine to display some values(33,67 etc).Where is the comparison with the adc value read in?For eg. if you want to display 33 if input voltage is 1V,you'll have to read the adc and compare the value read with 51 decimal(assuming you have left Vref/2 pin open,which gives a step size of 19.5mv thus giving a digital value of 51 for 1000mv input(adc value=Vin/step size)).If adc value is 51 then you call the data_display1 routine.Similarly for other Vin values.So make the necessary changes and get back to us. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 pdi33 hi priya,i have already mentioned earlier and would like to repeat that please mention the definition of various variables like rd/wr.etc. and also the hardware connections as that would help us understand exactly what logic u have applied in our code. it is always good practice to add comments whereever possible so that we can understand ur code better and provide some useful feedback. now, as far as ur problem is concerned, follow the following procedure, if possible:first temporarily remove the code which reads ur ADC.u can do that by just adding a semicolon before the ADC read instructions. and check the display code if it is working properly by outputing some fixed values to the display. Once it shows the correct values, reintroduce the adc value and put the values in the display routine.step by step troubleshooting would always save u a lot of time. good luck.P.S. look back in some posts by arun and shashi and u will find some really useful hints on how to correctly interface the LED display. read them carefully (note them down preferably as i understand u have a very slow internet connection) and try correcting the errors by urself. Please understand that if u can correct ur logical errors,( as far as possible) than that would benifit u the most and that is the sole intention of all of us here. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir, here i am describing the hardware connections of my project------------------FOR ADC(0804)PIN 20: supply voltage +5 voltsPIN 18---PIN 11:these are the data lines and are connected in the following wayPIN 18 CONNECTED TO PORT P3.0(microcontroller 8051)PIN 17 CONNECTED TO PORT P3.1PIN 16 CONNECTED TO PORT P3.2PIN 15 CONNECTED TO PORT P3.3PIN 14 CONNECTED TO PORT P3.4PIN 13 CONNECTED TO PORT P3.5PIN 12 CONNECTED TO PORT P3.6PIN 11 CONNECTED TO PORT P3.7PIN 1: CS is groundedPIN 2 :RD IS CONNECTED TO P2.5(PIN NO:26 OF MICROCONTROLLER 8051)PIN 3: WR IS CONNECTED TO P2.6(PIN NO:27 OF MICROCONTROLLER 8051)PIN 4: here i have provided external clock PIN 5: INTR IS CONNECTED TO P2.7(PIN NO: 28 OF MICROCONTROLLER 8051)PIN 6: here i have provided a variable input at which i am varying the voltage valuePIN 7: groundedPIN 8,PIN 10: grounded separatelyPIN 9: OPENVref: 1.28 volts FOR MICROCONTROLLER(8051):connections with ADC (0804) are already mentionedPIN 40: power supply +5 volts VccPIN 31: EA/VPP connected with pin 40here also i have provided external clock and build the reset circuitry with capacitors and pull -up-resistorsPORT PIN P1.0: segment A of seven-segment display (SP5503)PORT PIN P1.1: segment B of seven-segment displayPORT PIN P1.2: segment C of seven segment displayPORT PIN P1.3: segment D of seven-segment displayPORT PIN P1.4: segment E of seven-segment displayPORT PIN P1.5: segment F of seven-segment displayPORT PIN P1.6: segment G of seven-segment displayPORT PIN P1.7: segment H ofseven-segment displaySP5503 is a commoncathode chip so i have used common cathode configurationsir, this is my entire hardware connection,i have also tried to correct my code and so edited the post please go through it once.theanking u http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V PIN 18 CONNECTED TO PORT P1.0(microcontroller 8051)PIN 17 CONNECTED TO PORT P1.1PIN 16 CONNECTED TO PORT P1.2PIN 15 CONNECTED TO PORT P1.3PIN 14 CONNECTED TO PORT P1.4PIN 13 CONNECTED TO PORT P1.5PIN 12 CONNECTED TO PORT P 1.6PIN 11 CONNECTED TO PORT P1.7PIN 1: CS is groundedPORT PIN P1.0: segment A of seven-segment display (SP5503)PORT PIN P1.1: segment B of seven-segment displayPORT PIN P1.2: segment C of seven segment displayPORT PIN P1.3: segment D of seven-segment displayPORT PIN P1.4: segment E of seven-segment displayPORT PIN P1.5: segment F of seven-segment displayPORT PIN P1.6: segment G of seven-segment displayPORT PIN P1.7: segment H ofseven-segment displayin my last post i asked a question :1) Why in the world did you connect ADC & 7 seg display to the same PORT 1 ? use the ADC on some other free portArun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir,can u please provide me a brief description of the chip SP5501(common anode) or give me any link where i can get its detailed datasheet. thanking u. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir,please tell me where i can find the datasheet of SP5501 or please givemethe datasheet of any other chip equivalent tio that.i had gone through the site www.kwalityindia.com but i am unable to understand datasheet of which chip wil be equivalent to SP5501.please help. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 pdi33 hi priya, here is the clip for the connection diagram from the kwality.com site. use any one of the two displays as the connections are same. also the connections are same for common cathode and anode displays. these are equivalent of sp5501/5503. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 thanx a lot pdi33 sir,my project is still not working as arun sir suggested I have connected the seven-segment display to a separate port P3 and have connected ADC at P1 of microcontroller but still seven-segment display doesn't show proper results,it first shows 8 then 0 .It is not functioning according to the logic of my program,please helpme out sir. thanking u. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V Hello Priya,i appreciate your "Never Give up" attitude, i think the whole code is unnecessarily made complicated, here is my function steps to display 000 to 255 for voltage between 0-5 volts:1) wire the ADC in free running mode2) read ADC value from a port 3) call BIN2DEC routine to convert the ADC (Bin value) to Decimal value and store in three locations in RAM- Hundreds,tens,ones4) Call Seven segment display routine - display 1st digit,2nd digit,3rd digitmov r3,#00hmov a,#00hcjne a,#00,over1over1: acall data_display1 here even if Acc is 0 or not equal to 0, micro jumps to Over1. can you tell me what this routine does?how many 7 seg leds (digits) have you connected - single, two or threegive me the full details and i'll help you write the code here itself in the forum step by stepyour Circuit diagram would be appreciated one more thing, why are you confusing yourself and us by using Hex value sometimes and Decimal value sometimes for eg : you instr. : mov r3,#67h cjne a,#103 use either Hex or Decimal notation for these camparisionsArun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V Hello priya,to help you out from frustration, here is my code, i hope this solves your problem,stick to the comments in the program and rewire your connections if needded.tell me if you need any other changes, ideally i would display ADC value in Hex to BCD ( 000-255 ) on three 7 seg displays, but you are using single display and your logic is differenti have tested the code on my trainer board and simulator and it works as intended !: code deleted by ArunArun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir, in this project I am using a single seven-segment display,and in the earlier posts I have given the description of my entire circuit connection. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 thanx arun sir 4r ur code ,it helped me a lot but the fact is that it is not totally according to my circuit .I havementioned the logic of the program in the earlier posts.My problem is that the program code which I have written is simulated properly but when i am loading it onto the microcontroller chip and designing the entire circuit on the breadboard the seven-segment display does'nt work according to the circuit.ihave mentioned the circuit connections in the earlier posts.i am posting my program code .please help me to correct it tomake my circuit work. setb p2.5setb p2.6intr bit p2.7setb intradc_port equ p1 voltage_val equ r3adc_val equ 30hsevensegment_display equ p3sevensegment_val equ 19horg 0hstart: acall read_adc acall conversion mov p1,adc_val sjmp startconversion: clr wr setb wr read_adc: clr rd mov a,p1 setb rd mov r3,#01h acall data_display1 mov r3,#02h acall data_display2 mov r3,#03h acall data_display3 mov r3,#04h acall data_display4 mov r3,#05h acall data_display5data_display1: mov a,#33h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov p3#92h acall delay mov p3,#0f9h acall delay retdata_display2: mov a,#67h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov p3,#0f9h acall delay mov p3,#0c0h acall delay mov p3,#0b0h acall delay retdata_display3: mov a,#97h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov p3,#0f9h acall delay mov p3,#92h acall delay mov p3,#0f9h acall delay retdata_display4: mov a,#99h mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov p3,#0f9h acall delay mov p3,#92h acall delay mov p3,#0b0h acall delay ret data_display5: mov a,#0ffh mov b,#0ah div ab mov r7,b mov b,#0ah div ab mov r6,b mov r5,a mov p3,#0a4h acall delay mov p3,#92h acall delay mov p3,#92h acall delay ret delay: mov r4,#200 here: djnz r4,here ret org 19h seven segment_display: mov r1,#0 mov r2,#0c0 mov r1,#1 mov r2,#0f9 mov r1,#2 mov r2,#0a4 mov r1,#3 mov r2,#0b0 mov r1,#4 mov r2,#99 mov r1,#5 mov r2,#92 mov r1,#6 mov r2,#82 mov r1,#7 mov r2,#0f8 mov r1,#8 mov r2,#80 mov r1,#9 mov r2,#98 ret end http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V Hello Priya, i am sorry to say that this is one of the worst code i have seen so far, you ask why ?1) what ever variables you have declared are not used anywhere in the program2) what you want the code to perform is missing- objective is missing3) you are simply loading some preset values into the display port4) you are not comparing the ADC value to any known values5) when you convert binary to Decimal you should first divide by 100D (64H) ,later by 10D but you are dividing first by 10D and second also by 10D see here in your code 0ah i,e 10D:CODE:mov a,#33h
mov b,#0ah
div ab
mov r7,b
mov b,#0ah
div ab
mov r6,b
mov r5,a6) and what are you doing with these registers : R7,R6,R5 ?CODE:seven segment_display: mov r1,#0
mov r2,#0c0
mov r1,#1
mov r2,#0f9
mov r1,#2
mov r2,#0a4
mov r1,#3
mov r2,#0b0
mov r1,#4
mov r2,#99
mov r1,#5
mov r2,#92
mov r1,#6
mov r2,#82
mov r1,#7
mov r2,#0f8
mov r1,#8
mov r2,#80
mov r1,#9
mov r2,#98
ret

 7) what does this above Routine do ? - its rubbish 8) when a compiler compiles a code and outputs hex file, it doesn't mean that the code is error free - ever heard of "GIGO" term - "garbage In garbage Out"9) provide a flowchart or block diagram of your logic so that we can help, forget " i have posted my logic in earlier posts" statement , nobody can track each and every thread in a forum, Arun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 thanx a lot arun sir for tracking my mistakes,I am trying to build a data-acquisition system by using adc and microcontroller. i have already developed a look-uptable for the adc. providing a variable voltage at pin6 of adc i have found out the adc values by connecting all the datapins of adc toleds on my trainer kit.i am trying to programmy microcontroller in such a way that when i apply say,1 volts to adc the output should be 033h(according to the look-up table of ADC). i have connected pins of port1 of microcontroller to data pins of ADC. I want to see the display through seven-segment display ,so i have connected a seven-segment display(common anode type)to port p3 of microcontroller. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V Hello priya123,here is my code in two versions : ver A - displays 3 digit decimal on Common Anode Ver B - displays 2 digit hex value on Common AnodeverA : : code deleted by Arunand here is want you desperately wanted Ver B : : code deleted by ArunHope this solves your long time problem !Arun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 nischay kumar hello sir,your program works perfectly, i have tried it and have learned new concepts in asm programmingnischay kumar http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 thanx arun sir,your program code really helped me a lot,but still there is one doubt which i want to make it clear . i am using ADC(0804) in free-running mode. I have connected it to microcontroller(89s52) in the following way: ADC(0804) pin no:1 -------- CS groundedpin no:2---------rd connected to port pin 2.5pin no:3---------wr and pin no:5--------------intr shorted together pin no: 3 ---------------wr connected to port pin 2.6 of microcontrollerpin no :5----------------intr connected to port pin 2.7 of microcontrollerpin no:6 ------------- variable input ,voltage is varied herepin o:7--------------- groundedpin no:8-------------------- groundedpin no:9------------------- vref (1.28v) ,i have left it openpin no:10------------------groundedpin no:11 to pin no:18 (data pins) connected to pins of port1 of microcontrollerpin no: 19 -------------- connected to external clockpin no:20--------------+5 volts vcc. sir please tell me whether this connection is correct? if incorrect,then what corrections should I make?please help. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V Hello priya123, very late reply, about the ADC in free running mode , your current setup is not Free running mode- in the free running mode, the ADC constantly converts the analog voltage at its input without the micro sending control pulses. one conversion triggers another conversion without micro's interference.i have already described the connections of ADC in my above code:;***************************************************************************; ADC 0804 IS CONNECTED IN FREE RUNNING MODE; VREF IS CONNECTED TO +5VOLTS;; GROUND PINS CS,RD,Vin-,DGND,AGND ON THE ADC; CONNECT WR PIN TO INTR PIN ON THE ADC;****************************************************************************you only need to connect ADC's (D0-D7) Data bus pins to the micro's port, in your case its Port1.when ever you want to read the input voltage , you just Mov contents of Port1 to Accumulator or any other Register.interval between two readings should be atleast 1 uSec, which is not a problem when using normal 8051 @ 12 Mhz clock rateArun http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 sir,please provide me the pin configuration of LM35 and LM34 sensors or sir,please give me any link from where I can get the pin configuration. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 sashijoseph Look here : http://www.facstaff.bucknell.edu/mastascu/elessonshtml/Sensors/TempLM35.htmlGoogle will give you umpteen links...do use it. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 priya123 hello sir, thanx for ur information on LM 35 sensors,could u provide me some more information about LM 34 sensor(fahrenheit sensor) ,its pin configuration and characteristics. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 mohannad100 hi mr aruni need help in my problem,i have connected a thermocouple through amplification circuits and then the voltage is input to adc0804 ,i need a code to display the variouse temperature measurements that reads by adc0804 throgh 8051 on 4 digits 7 segments display(one piece)i hope the replay thanks. http://www.8051projects.net/forum-t9400.html 2008-12-02T00:35:26-08:00 Arun Kumar V Hello friend,Pl. check my previous posts in this thread (page 4) i have already given the full codes with comments, they are for single 7 seg LED display but you can modify for 4 digit display.you may have to use a look up table for displaying conversion results.Arun