Matrix user forums

well after checking it step by step i found that indeed that was the mistake with the algorithm and it's fixed, and working, thanks alot!

hi yes about the keypad forgot to change the silks screen on the simulation, well i have taken 2 photos, one of the simulation and the result on matlab (the 2 parameters are shown on the matlab photo they are absolutely the same), the results are the same on both, and a picture of the real project (...

hi, after some small modifications i actually noticed that the program doesnt work, everyhing seems fine but the final results of the calculation are wrong (but the simulator gives the right answer), i tried it with 2 16f877a and one 18f4455, so the chip is not the problem and i dont know what cause...

hi

i got it working it was the connections, i hook the pulldows incorrectly (to the columns) now it's working thanks alot

well i have tested the keypad and the connection is fine, and with a very simple program and it works fine, but the strange thing, this program on the simulator (proteus) with the 16f877a it warns me that it's trying to simulate memory that's not implemented, with the 18f4455 on the simulator it goe...

hi, i am having trouble with this code, it's a convolution calculator, a relatively simple operation, (the code is kind of messy and it has to be optimized) on the flowcode simulator it works fine, when i tried it on proteus, it gave me warnings about the memory (on the 16f887a) but when i test it o...

well i noticed that using the output icon disables the WPU and apparently also the interrupts, so i am switching the direction using the tris registers, and it works, the isr gets serviced, it's just that it is only doing half of the code, unless i press the key several times very quickly, another w...

hi i am having trouble with the interrupt on change, C code trying to make a matrix keypad the lower part of the port is an output and the ioc pins inputs, the idea is to read the columns on the isr, then change the direction so that the outputs are inputs and do the same, the OR them together and i...

hi i am trying to read a keypad with interrupts on a pic 16f877a (mainly because polling is to slow), to read it i am using the internal resistors, the columns are connected here (RB4-7), the LSB are outputing a logical 0, so when i press the key the interrupt occur, then in the isr, first i dissabl...

thanks alot that was the problem, now it's fixed thanks alot

hi, i have been trying to use a matrix keypad, i have used the examples provided here, and when i simulate it with flowcode an proteus it works, but on a breadboard, it always sends me several keys (i remember that it always send 4 7 and 1), as if i where pressing them, i tried changing the port add...

thanks alot ben just what i wanted to do

Hi i been having trouble doing a simple task, i want to send a message to a lcd using a button (any port) and do nothing, then using the same button send another one one line below, so i can see the two messages, but i cant figure out how to do this because every time i try with the button (momentar...

Hi i want to use this GLCD http://www.ebay.com/itm/132x132-pix-Serial-Color-Graphic-LCD-SPI-PIC-ARM-AVR-/400078962224?_trksid=p5197.m7&_trkparms=algo%3DLVI%26itu%3DUCI%26otn%3D4%26po%3DLVI%26ps%3D63%26clkid%3D2372855289256398022 but i want to know if the lcd can be driven directly with the GLCD macr...

ok, yhanks alot this was very helpful

hi i am trying to create a sine wave using the DAC0800 or using the pwm with capacitor method, but i have no idea how to do it, i want to use arrays but i am having difficulties using them so i am planing to send the outputs directly and with a loop, any infor would be great

Thanks alot, i was connecting the Lcd as the bits as the connections show it, and not to the uppernibble, thanks Benj you saved me , and thanks alot medelec35 your advices were very helpful as well

by the way maybe this is the problem, the lcd that i am using (16x2) is a TC1602A and the 16x4 is a kl sn102 94v and a pwb 20434-cem

hi thanks for the advice and the link i checked the settings and they are correct, using a cristal of 4Mhz, and double checked the connections and it still doesnt work, i am uploading the code

well i amo not using Eblocks, i am testing it on a protoboard, and i have followed the conections (RW to GND) but it doesnt work, i am using the f877A and the ldc is on port B and it still doesnt work

by the way i checked the oscillator frequency and it matches my current oscilator (XT)

thanks alot!

hi, i have been trying to connect the lcd to the pic 16f88 and 16f877A but non shows anything on the lcd, i connect them to port B as default, but i doesnt work and i have been tryng several lcd displays (16x4 and one 16x2 the displays works so that's not the issue), so is there anything i should kn...

hi i am trying to create a electronic lock, using a keypad, using 3 numbers (170 by the way), but i am not able to "memorize" each pulse and it's value, and i dont know how to make the comparison so it can accept or reject the password, (i am using 2 leds as outputs)