polulu a4988 driver

-

hello, i've question,

does know why when put voltmeter probes on gnd pin , potentiometer realding goes few milivolts(the reading when electrodes in air) complete zero?
 
while im testing have connected should be, every voltmeter try show same things. (i'have tried 3 or 4 different multimeters, tried ac voltmeter:d).

at first thought drivers somehow damaged , unlikly because motors turning. , tried using oscilloscope , got reading.

(i have adjusted potenciometers, im curious why doesnt work vltmeter)

oh , if knows correct vref equassion accurate, realy use one, because have seen two, 1 in howtomechatrinox.com way off, , 1 allways whenever different datasheet on a4988 (i rated =v ref/(8 * r sense). did not work,  motors started shiver after set current twice high equassion said

my google shoots me directly pololu site, find formula:

quote
current limit = vref × 2.5
this applies if have original pololu a4988 0.05Ω current sense resistors.


Arduino Forum > Using Arduino > Motors, Mechanics, and Power (Moderator: fabioc84) > polulu a4988 driver


arduino

Comments

Post a Comment

Popular posts from this blog

Valutazione Template - Joomla! Forum - community, help and support

-
salve, prima di installare joomla, vorrei porvi tre semplici domande: 1) l'ultima versione in italiano di joomla, supporta questo template prodotto da gavik? loro scrivono che non è un semplice template, ma una vera e propria suite, ma vorrei una vostra opinione. qui sono descritte le funzioni della suite. 2) per sfruttare gli elementi che si vedono nella pagina, ad esempio quello in alto sinistra dove scorrono le notizie, occorre installare qualche componente aggiuntivo? 3) futuri upgrade alla piattaforma joomla, potranno inficiare il funzionamento o la compatibilità del template? vi ringrazio anticipatamente della disponibilità. 1) non vedo nulla di particolare se non una miriade di posizioni per blocchi 2) è un modulo se non sbaglio pagamento, ma adesso non ricordo bene 3) no. ti ricordo che devi installare joomla  1.0.12 Board index Joomla! International Language Support International Zone Italian Forum ...
Read more

SD Datastring Convention

-
i wondering if there preferred convention appending data logged?  see standard sd example uses: code: [select] void loop() {   // make string assembling data log:   string datastring = "";   // read 3 sensors , append string:   (int analogpin = 0; analogpin < 3; analogpin++) {     int sensor = analogread(analogpin);     datastring += string(sensor);     if (analogpin < 2) {       datastring += ",";     }   } creating string called datastring, , appending it, have seen in forums string not liked.  around this, code data logging looks this: code: [select] void sdupdate() {   datetime = rtc.now();   unsigned int hour = now.hour();   unsigned int minute = now.minute();   unsigned int second = now.second();   char datastring[100] = "";   char char_current_pay[15] = "";   char char_overall_pay[15] = ""; ...
Read more

First use of Arduino Uno : avrdude error on Blink uploading

-
hi all, i bought arduino (or should genuino) starter kit. first test , failing. i have follow religiously first pages , when trying upload blink sketch, uploading fails avrdude error : avrdude: stk500_recv(): programmer not responding. as suggested in other posts, have tried 1) switch latest hourly build of arduino ide 2) switch previous stable version of arduino ide (1.6.09) 3) change usb cable 1 know working fine 4) make same steps on computer (unfortunatelly, of them macos running on macos 10.11.6, not interesting test) 5) press reset before upload, interesting thing : tx led never flashes the full log attached. idea of why happening ? to save people having download log, it's sync error, resp=0x00 every time: code: [select] avrdude: stk500_recv(): programmer not responding avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x00 avrdude: stk500_recv(): programmer not responding and he's running 1.6.11 hourly avrdude 6.0.1. ...
Read more