bioprof Posted February 11, 2009 Report Share Posted February 11, 2009 bonjour,I'll try to write in english.I read tongenerator pb and it looks like mine.My midibox : coredout with two interruptsdin with 64 ledsI tried dout_button test and , when i start midibox, mios don't load and all leds are lights.When i try the same with only one dout x4 and the first shift register on it, the test works fine ( one led lights sequentially with one interrupt).I must to say i have wired badly the dout the first time and i wondered if i had not burn the shifts registers ( especially sclk and rclk because they "taked 5V on the teeth" the first time :-[). Quote Link to comment Share on other sites More sharing options...
/tilted/ Posted February 11, 2009 Report Share Posted February 11, 2009 Sclk and Rclk INTO a DOUT board should be fairly robust.By this I mean they are meant to take signals up to around 5V as part of their operation, so feeding them a constant 5v is not so bad.However, if you have shorted sclk and rclk to 5V, you could damage the PIC, by holding a driven pin to a voltage level. I'd imagine the PIC has a certain amount of protection against this... Anyway, if you had damaged the PIC, then sclk and rclk would not work, and no dins or douts would work as a result.Try one DOUT board at a time (as you have). The next step is finding out which board is bad, (the one which makes it stop working), and figure out what is wrong with this board.EDIT: Formatting... Quote Link to comment Share on other sites More sharing options...
cimo Posted February 11, 2009 Report Share Posted February 11, 2009 Tilted 1 -- Cimo = 0 >:(dout with two interruptsdin with 64 ledsthis is incorrect, just a typo?I must to say i have wired badly the dout the first time and i wondered if i had not burn the shifts registers ( especially sclk and rclk because they "taked 5V on the teeth" the first time Embarrassed).that should n t be a problem, but i ve destroyed some 74165s just with staticI tried dout_button test and , when i start midibox, mios don't load and all leds are lights.When i try the same with only one dout x4 and the first shift register on it, the test works fine ( one led lights sequentially with one interrupt).Can you try to swapt the 2 SRs on both the placements? In this way you can bu sure if they are ok or notSimone Quote Link to comment Share on other sites More sharing options...
bioprof Posted February 11, 2009 Author Report Share Posted February 11, 2009 hello,i am so confuse .two interrupts in din and 64 leds dout.I tried to swapt all of the SR's but it works with only the first alone. Quote Link to comment Share on other sites More sharing options...
stryd_one Posted February 11, 2009 Report Share Posted February 11, 2009 Did you swap:Just the SR chipsThe SR chips and the boards they are inThe SR chips and the boards they are in and the cables connected to that boardTry them all ;)And remember - each test should be the result of ONE change. Be methodical, and record all of your results. Quote Link to comment Share on other sites More sharing options...
bioprof Posted February 12, 2009 Author Report Share Posted February 12, 2009 hello,i have read something like that in midio128 page :" It's only important that the last input shift register is terminated with ground level (0V), so that the firmware doesn't recognize invalid values."there something with my probleme and somebody could explain what does it mean. Is the last input SER or O8 ?How to put that on ground ? Quote Link to comment Share on other sites More sharing options...
seppoman Posted February 12, 2009 Report Share Posted February 12, 2009 " It's only important that the last input shift register is terminated with ground level (0V), so that the firmware doesn't recognize invalid values."there something with my probleme and somebody could explain what does it mean. Is the last input SER or O8 ?How to put that on ground ?I guess that's a small documentation error and TK is talking about the SR chain pullups. These are R33-R36 in the DIN schematic (http://www.ucapps.de/mbhp/mbhp_dinx4.pdf). They make sure that the chain input of the last 165 chip (SER) isn't floating, i.e. doesn't detect random input events when no other 165 is feeding that input. If you put GND to that last SER input, it would make the box send note ons for the rest of the (nonexistant) chain, so it should read "It's only important that the last input shift register is terminated with a 10k pull up resistor to VCC on its SER input, so that the firmware doesn't recognize invalid values." Quote Link to comment Share on other sites More sharing options...
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