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 2009-01-08T11:10:32-08:00 contact@nospam.com hourly 1 2000-01-01T12:00+00:00 http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Hey friends,I have already discussed about the Roman Black's BTc Algorithm.. here is a working demo of it.. I know there might be some modifications needed with the design and some other modifications..This one i directly input the sound from controller to my MIC and recorded it.. no coupling used.. I am still looking for a speaker which can play the sound with good volume level (suggestions needed). also i need suggestion to make a good audio circuit I am actually thinking to make a talking clock.. so in my sample program.. i counted from 1 to 59 and its working pretty well.. the code is about 24KB (including all sound samples)here is a demo of The Talking 8051.http://www.8051projects.net/sound/count.mp3Please compromise with the voice quality after all.. its an 8-bit controller http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 abbas1707 Nice work Ajay Are u going to put it to project section?? i realy want to learn about it http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 ۞ TPS ۞ hi interesting project 1. you can use 2" 0.5Watt speaker2.for more audio you can use LM386 as an amplifier also i heard the sound i think a LPF is needed PCB - for amplifierplease use 0.1 uf capacitor as coupling capacitor to input http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Ajay sure i will post it just wait a while.. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Arun Kumar V Hai Rickey,Its been 6 months since you posted this idea, any new developments in this regard,and when can we seen the project/algorithmbyearun http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Ajay i donno where can i find these ICs.. coz where i stay you hardly find something over there.. even to get a controller you need to travel for about 2-3 hours.. even though this method is not so good but i had to use it..there is still more space for advancements, i am not getting enough time. busy in some other projects.. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Amit Radha Hey Ajay,I think this has been done as a project in my college as "uC based watch for the visually handicapped".As far as i understood it, 2 cards had been used with stored sound bytes and these were picked up by the uC and played from those pre specified locations.The 2 cards they used were 100% bought (could make out when i saw it) but itseems they had done the rest of the interfacing and coding.I could try looking into it if u need some more specifics! (For that il have to hunt in the my dusty dingy college library) http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Chiru In that case things can be made simple by using voice recorder chips like APR6016, APR9600 etc, and interfacing with a uC http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 sashijoseph You can get them here : http://aplusindia.net/aplusindiauser/ShowProductAction.apu?cat_id=51 http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 sashijoseph 15625Hz = 64usec not 32.For 64us,TH0 =0xFF,TL0 = 0xC0.Also put your main routine beyond 13H or the ISR space will be overwritten by your main. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Arun Kumar V here's my code to generate sound on a 8051; $MOD51OUT EQU P3.0DSEG ORG 0020HCOUNT: DS 1CSEG ORG 0000H ; ON RESETJMP MAINORG 000BH ;Timer Interrupt0JMP PLAYMAIN: MOV SP,#40H MOV COUNT,#00H MOV DPTR,#VOICE MOVC A,@A+DPTR MOV TMOD,#02D MOV TH0,#0E0H MOV TL0,#00H SETB EA SETB ET0 SETB TR0 LOOP: SJMP $;***********************************************************************************; ISR FOR TIMER0 ;***********************************************************************************PLAY: INC COUNT MOV R3,COUNT CJNE R3,#09D,ACTION MOV COUNT,#00H INC DPTR LINE1: CLR A MOVC A,@A+DPTR CJNE A,#99H,ACTION MOV DPTR,#VOICE SJMP LINE1 ACTION: RLC A MOV OUT,C RETI ;*********************************************************************************** ORG 0250H VOICE: DB 00000000b ; 00 DB 00001110b ; 0e DB 01111011b ; 7b DB 01001100b ; 4c DB 10101101b ; ad DB 01001101b ; 4d DB 01110101b ; 75 DB 00000101b ; 05 DB 01011101b ; 5d DB 10101010b ; aa DB 01010101b ; 55 DB 10101101b ; ad DB 01001010b ; 4a DB 10100100b ; a4 DB 10110001b ; b1 DB 01000101b ; 45 DB 01111001b ; 79 DB 11000111b ; c7 DB 00111101b ; 3d DB 01000011b ; 43 DB 01010101b ; 55 DB 11000111b ; c7 DB 00011100b ; 1c DB 01110001b ; 71 DB 10001110b ; 8e DB 00110000b ; 30 DB 10100111b ; a7 DB 00111001b ; 39 DB 11001111b ; cf DB 00011010b ; 1a DB 11111000b ; f8 DB 11000010b ; c2 DB 99HENDi don't know what the problem is, the result is some hissing noise i get from speaker.iam using Xtal 12Mhz, interrupt is generated every 32uSecs i,e 15625Hz.the data table is very large i've inserted only a block here, i am using 99H as EOC checking. can some one point out the bug ( i am doubting the Timer0 ISR)arun http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Arun Kumar V Hi Sashi, thankx for the early reply ! 1) this is how i calculated delay time : T= 1/15625 = 64u Sec , 64/2 (half of it) = 32uSec high portion and 32usec Low portion of the pulse. i may be wrong 2) iam using Timer0 in mode 2- Auto reload ,8bit timer mode ,so that the uC doesn't have to reload T values every time (saves time) 3) about the ISR for Timer0 , there is only one Line instruction i,e JMP Addr at the Interrupt Vector space , so no question of Overwriting4) i am using 99h as check for End of Character (EOC), this value may be present in the data table causing premature exit of the program. what other Value or character can i use to know the end of Data table Good News, i have changed the interrupt delay from 32 uSec to 64uSec and i could hear 8051 talk for the first time sound Quality is bit rough but speech is understandable! Cheers to ROMAN BLACK Arun http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Ajay This is what i have found after using his algo..no need to use 1.5 bit algo, use 1 bit algo instead.in my first post i used 1.5 bit algo and there is lot of beeping sound in the o/p. this sound can be significantly removed if we are using 1bit algo. simply replacing series of 1's with 0's.. i mean look for FF in data and replace it with 00.Only thing we need to work on is.. sound quality..or any external thing we can do to improve the quality. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 sashijoseph You could try adding a 2-pole active LP filter at the o/p.Would remove most of the HF artifacts. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Ajay hmm... i am bad at filter designing http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Chiru Hi Ajay, contact Mr. Viral @ 0 9825858509 http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Chiru I mean, contact him if you want those audio chips delivered to you, i mentioned earlier. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Ajay thanks chiru http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Arun Kumar V HI, to remove the Hi-freq, i have used 2 stage LPF with and inductor, for my particular Playback Rate i have used something like this: --------4.7K--------- * ---------1.5k--------* ---------1.5uH(indcutor)------>To Amplifier ' ' ' ' ' ' = ( 220nf) = (100nf) ' ' ' ' ' ' Gnd Gndwith this circuit iam able to remove most of the squeal, in the Amplifier i completely turndown the Tone control and Set Bass to mid way.Hey guys , my problem of finding End of Character (EOC) at the end of table still remains unanswered ! what value can i use to Check the End of table so that i can Loop the Message http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 sashijoseph Any value you use could possibly be a 'sound byte'.So to minimize errors you could use 2,3 or 4 signature bytes and check for all of them in sequence before terminating.Or if you know he total no. of sound bytes you could use a counter set to that value, decrementing it with each byte played. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Arun Kumar V Thankx Sashi, i'll try that, BTW i was thinking of using the spare timer to keep track of the length of the message ,if i know the duration of the message played for eg. 5 secs, i can reload the DPTR to the first value of the table after completion of 5 every secs . to get 5 sec delay i could use a tick of 50msec(interrupt @ of 50mSec) and a counter for 100 will give 5000msecs.arun http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Arun Kumar V Hello forum,as posted earlier i have success with BTC encoder using 8051 single port pin playback,the audio file is sampled at 15625Hz, played back on a port pin @15625 bits per sec, the BTC encoder outputs the audio into stream of 1 bits which need to be played back using interrupt now i want to playback using a 8 bit DAC, to playback the BTC encoder 's 1-bit stream but i have few doubts :1) instead of playing 1 bit at a time @ of 15625 Hz, can i play 8bits @ 15625/8 Hz i,e 1953 Hz ? will this give same output2) will using DAC improve playback clarity ?Arun http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Arun Kumar V Hello think tanks ,any comments on my last postArun http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Ajay well you need to do 8-bit sampling, just like PCM wav sound its much more clear but the thing is it takes lot of memory.. you might need an eeprom to store data then..can be a good project if you can implement playing a wav file stored in eeprom and then playback using 8051 also you can try recording also.. via adc, sample it at 8k and then store that 8-bit data http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Arun Kumar V Thanks AjayArun http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 GioppY Years ago i built a simple(no uC, only counter and eprom) wave player.Wave files are resampled at 8KHz and converted to SND then are stored in eprom(27c256/512/1024)Obviously this is usefull only for short sound.RegardsP.S.If someone want play with it i have the schematic somewhere http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Arun Kumar V Hello Guys, since past 2 weeks i have been working on Roman black's BTC encoder since i didn't want to give up so easily, here are my findings :1) the output file by the encoder is nearly 1/8th size of the original file - how does he do it? simple , 8:1 Compression , he selects the first MSB of the 8 bit sample and knocks off the remaining 7 bits of the sample byte. 2) clarity Issues - the clarity we get when a sound is played at 8Khz with 8bit sampling can be achevied on BTC but you have to choose to sample it at a very high rate of 48Khz (i,e 8 times faster) to get the same clarity, again you this won't reduce your output file size, for eg: 1 sec sound at 8Khz, 8 bit has 48,000bits file size same with BTC encoder a 1sec sample at 48Khz rate has 48,000bits file size. so if you want clarity then your BTC doesn't Help you reduce the file size3) don't get carried away when you select sample rates like 15,625Hz, 22,050Hz etc in BTC options - a 8Khz, 8 bit sample sounds a lot better than 15,625Hz,1 bit BTC sample Why ? in reality it BTC plays the sample at 15,625/8 Hz rate i,e 1,953Hz , 8 bit sample which is creepy when compared to original 8000Hz, 8bit sample 1) instead of playing 1 bit at a time @ of 15625 Hz, can i play 8bits @ 15625/8 Hz i,e1953 Hz ? will this give same outputi got my answer, YES, it can be played but it gives same harsh sound quality.hope these findings might help someoneArun http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 anee hey arun....i m not gettin a hang of da btc software...i mean it does convert da wave file into a binary output...but how do i store these values in 8051...how do i get da hex vaues for da look up table...i know dis is a dumb doubt...but i m a newbie.. ...do reply...thanks in advance.. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 pdi33 GioppY wrote ...Years ago i built a simple(no uC, only counter and eprom) wave player.Wave files are resampled at 8KHz and converted to SND then are stored in eprom(27c256/512/1024)Obviously this is usefull only for short sound.RegardsP.S.If someone want play with it i have the schematic somewherehey Gioppy,I would certain;y like to see how u stored it in the eprom without a uC . Can u send me the schematic or tell me about the logic?thanks in advance http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 sashijoseph Here's one....... http://web.telia.com/~u85920178/eprom/wave_00.htm http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 pdi33 hey thanks shashi for the link. hmmm, actually i did not notice the "27c256/512/1024)" part and was thinking how on earth can u store data in a serial eprom w/o a uC or uP.anyways the idea is cool. will try it out sometime. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 GioppY I would certain;y like to see how u stored it in the eprom without a uC . Easy! The eprom must be programmed with an external programmer.The 27Cxxx eprom seriers are UV erasable electrically programmable eprom http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 pdi33 hmm nice one. interesting how u used the 555 timer in this one. thanks gianni. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 sashijoseph Yeah,nice one Gianni. http://www.8051projects.net/forum-t2092.html 2009-01-08T11:10:32-08:00 Ajay very nice design really impressed..