A theoretical question

-

hi,
i wondering why have use pinmode declaration in sketches. if use analogwrite or digitalwrite command specific pin, doesn't imply particular pin output? , if use read versions of similar command, doesn't imply opposite?

thanks

quote
doesn't imply particular pin output?

using analogwrite(), yes. using digitalwrite(), no. might turning pullup resistor on input pin.

quote
and if use read versions of similar command, doesn't imply opposite?

pins default input, read works without need use pinmode(). in fact, though, can read state of output pin. so, digitalread() rells nothing state of pin.


Arduino Forum > Using Arduino > Programming Questions > A theoretical question


arduino

Comments

Post a Comment

Popular posts from this blog

VIDIOC_S_FMT error 16, Device or resource busy - Raspberry Pi Forums

-
dear all, working on image processing using raspberry pi, have installed intex usb web camera on raspberry pi. have used basic python script of image processing https://www.cl.cam.ac.uk/projects/raspb ... first.html required libraries installed on raspberry pi. script code: import imgproc imgproc import * # open webcam take pictures camera = camera(160, 120) # open viewer window display images viewer = viewer(160, 120, "the first step") # take picture camera img = camera.grabimage() # display image in viewer viewer.displayimage(img) # iterate on each pixel in image x in range(0, img.width): for y in range(0, img.height): # value @ xth column , yth row, place intensities variables red, green, blue = img[x, y] # test find colour dominant if red > green , red > blue: # red dominant, set pixel red img[x, y] = 255, 0, 0 elif green > red , green > blue: img[x, y] = 0, 255, 0 else: # if red or gr...
Read more

using a laptop skeleton to build a pi laptop - Raspberry Pi Forums

-
Image
i have laptop dead motherboard . can remove components laptop , in anyway possible connect raspberry pi inbuilt display , keyboard on laptop ? (and touchpad if possible). (i figured remove components inside , fix pie inside , use extended usb cable , connect available usb ports respective holes in laptop skeleton, same headphone out ) . i'm noob when comes pi . on topic appreciated if screen lvds type may possible use screen installing converter board. this: http://www.ebay.com/itm/hdmi-dvi-vga-dr ... 3027&rt=nc need model number of screen , ask seller if work. or search ebay using brand , model number. assuming screen in working order..... back-light not burnt out etc.. other devices...... can used if have usb interface not part of motherboard. have make connector. raspberrypi
Read more

Smoothing Capacitor value?

-
Image
hi everyone! i have question "smoothing capacitors". have 5v arduino project have 6 individual 5v components attached it. since need these running @ different times, wanted take similar approach of nick gammon's in helpful example (http://www.gammon.com.au/forum/?id=12106) , use few mosfets switch these little guys on & off individually (instead of regular arduino pins), while minimizing potential power surges affect microcontroller and/or components themselves. these components 5v, , have maximum draw of ~170ma when powered on @ same time. so, if used 6 different mosfet switches turn switch +5v power line on each component directed via arduino uno, wondering: 1. still use 1 capacitor (like nick did in example)? 2. capacitor of 100uf work, or should use bigger? my plan first test circuit mosfets & capacitor(s) using usb, , later on, moving project battery power. thanks in advance ideas & suggestions! quote these little guys what ...
Read more