radiotron Posted December 20, 2009 Author Report Share Posted December 20, 2009 (edited) ok so i've been checking and rechecking J1 for two hours! but i definitely have a short between SO and S1 on top of J1 does that mean the problem is somewhere else on the CS pcb or should i keep working on the J1? Edited December 20, 2009 by radiotron Quote Link to comment Share on other sites More sharing options...
Wilba Posted December 20, 2009 Report Share Posted December 20, 2009 To be sure it's definitely on the CS PCB, remove it from the base PCB and check. If there's a short while it's removed, then it's obviously on the CS PCB. If there isn't a short when it's removed, it could be on the base PCB (between pins of J8/J9 or near the PIC pins they connect to) so check for the short on the base PCB with the PIC removed. If there's no short on either when it's disconnected, then the short is happening by something else touching those pads while the PCBs are attached. Unlikely but possible. On the CS PCB, it could be on the bottom of J1, although that's unlikely as you'd need a lot of solder to fall through the holes and build up under the PCB. SO and SI are only close together at J1 and also at J2 (top right corner) but J2 is an unused header and you wouldn't have soldered there. Confirm where the short is (CS or base) and I'll come up with some more ideas. Quote Link to comment Share on other sites More sharing options...
radiotron Posted December 20, 2009 Author Report Share Posted December 20, 2009 ok so it's short on the CS and base! which pin on the PIC socket should i be testing? had a look under J1 quite a bit of solder coming through from the top but nothing touching Quote Link to comment Share on other sites More sharing options...
Wilba Posted December 20, 2009 Report Share Posted December 20, 2009 ok so it's short on the CS and base! which pin on the PIC socket should i be testing? had a look under J1 quite a bit of solder coming through from the top but nothing touching So you found shorts between SO and SI on both PCBs after they were disconnected? Did you take out the PIC first? And also, when testing for shorts on the CS PCB, did you remove the ICs? Seems very unlikely that you have shorts on both PCBs between the same two pins/tracks. How are you testing if they are shorted? SO and SI are connected to pins 19 and 20 of the PIC, you can refer to the Core schematic, headers J8/J9 are the same on sammichSID: http://www.ucapps.de/mbhp/mbhp_core_v3.pdf Quote Link to comment Share on other sites More sharing options...
radiotron Posted December 20, 2009 Author Report Share Posted December 20, 2009 i'm doing all these tests in continuity mode i think the base is fine cause i get a connection between SO to pin 19 of the pic and SI to pin 20 to test the SO and SI on the CS pcb i was probing those two points at J1 assuming they were meant to be connected not so much now that you've told me the IC's need to be removed... i'm learning tonnes about trouble shooting (which i've been lucky to avoid in the past!) Quote Link to comment Share on other sites More sharing options...
SLP Posted December 20, 2009 Report Share Posted December 20, 2009 This is what you should get. so the sammich-SID is more like a SID-KITT :D Quote Link to comment Share on other sites More sharing options...
Wilba Posted December 20, 2009 Report Share Posted December 20, 2009 To be perfectly clear... SO should not be connected to SI (on base or CS PCB). Similarly, any pin with a label (like RC, SC, Vd, Vs) should connect to other pins with the same label, and NOT to anything else. SO should be connected to PIC pin 19. SI should be connected to PIC pin 20. RC should be connected to PIC pin 15 21. SC should be connected to PIC pin 16 22. The above tests are hard to do between the CS and the PIC (i.e. with the PCBs attached), but if you validate base PCB J8/J9 carefully and also CS PCB J1, you can safely assume there's nothing wrong with the actual headers "mating" and thus the PIC pins are being connected to CS PCB correctly. Then you could move on to other places, like solder joints of IC sockets on CS PCB. I suggested taking ICs out of CS PCB just to be sure... it is more important for the PIC because there is some conductance inside the PIC between its pins... I didn't know you had continuity mode on a multimeter. Take both PCBs apart and retest each pin of base PCB J8/J9 and CS PCB J1, making sure it is not connected to adjacent pins. You can put some spare header pins into J8/J9 for easy testing. You really should do all the tests and list them here so I know what you have done already, it's hard to help if I don't know exactly what you have definitely tested is NOT a short or break. Quote Link to comment Share on other sites More sharing options...
radiotron Posted August 19, 2010 Author Report Share Posted August 19, 2010 ok so after leaving this in the too hard basket for aaaaggees i'm trying to get this up and running so this is where i'm at: To be perfectly clear... SO should not be connected to SI (on base or CS PCB). CHECK! Similarly, any pin with a label (like RC, SC, Vd, Vs) should connect to other pins with the same label, and NOT to anything else. CHECK! SO should be connected to PIC pin 19. CHECK! SI should be connected to PIC pin 20. CHECK! RC should be connected to PIC pin 15. this is not working SC should be connected to PIC pin 16. also not working i've checked the soldering on pin 15 and 16 on the PIC socket legs and they are fine what else can i check to get RC /15 and SC /16 connected? cheers simon Quote Link to comment Share on other sites More sharing options...
Wilba Posted August 20, 2010 Report Share Posted August 20, 2010 I don't know what drugs I was smoking when I said RC should be connected to PIC pin 15 and SC should be connected to PIC pin 16. This is totally wrong. RC should be connected to PIC pin 21. SC should be connected to PIC pin 22. In case you didn't know, pins 21-40 are on the other side of the PIC, with pin 21 at the bottom (opposite pin 20), pin 40 at the top (opposite pin 1). Refer to the Core schematic for clarity... you're testing PIC to J8/J9 header: http://www.ucapps.de/mbhp/mbhp_core_v3.pdf Check RC/SC again... between the PIC and the top of the CS PCB (when connected, obviously). Also check there is nothing shorting between RC, SC, SI, SO, 5V, GND. Quote Link to comment Share on other sites More sharing options...
radiotron Posted August 23, 2010 Author Report Share Posted August 23, 2010 I don't know what drugs I was smoking when I said RC should be connected to PIC pin 15 and SC should be connected to PIC pin 16. This is totally wrong. RC should be connected to PIC pin 21. CHECK SC should be connected to PIC pin 22. CHECK In case you didn't know, pins 21-40 are on the other side of the PIC, with pin 21 at the bottom (opposite pin 20), pin 40 at the top (opposite pin 1). Refer to the Core schematic for clarity... you're testing PIC to J8/J9 header: yes http://www.ucapps.de/mbhp/mbhp_core_v3.pdf Check RC/SC again... between the PIC and the top of the CS PCB (when connected, obviously). this is also fine (testing without pic insterted) Also check there is nothing shorting between RC, SC, SI, SO, 5V, GND. CHECK ok where to now? thanks Quote Link to comment Share on other sites More sharing options...
Wilba Posted August 23, 2010 Report Share Posted August 23, 2010 So getting back to your original reports... you said SO and SI were shorted... are they still shorted? did you fix this already? i.e. where were they shorted? CS or base? Moving forward :D try to get the LEDs working first since you'll know when they do, they'll match nILS video. Check for shorts between any adjacent pins of the two 74HC595 (top right of CS PCB) and the 220 ohm resistors and the LEDs. Quote Link to comment Share on other sites More sharing options...
radiotron Posted August 24, 2010 Author Report Share Posted August 24, 2010 So getting back to your original reports... you said SO and SI were shorted... are they still shorted? did you fix this already? i.e. where were they shorted? CS or base? they are fine i thought they were supposed to be connected so i thought it was a short! Moving forward :D LOLZ try to get the LEDs working first since you'll know when they do, they'll match nILS video. Check for shorts between any adjacent pins of the two 74HC595 (top right of CS PCB) and the 220 ohm resistors and the LEDs. noticed that i hadn't even soldered in S12!!! got excited fixed it put it together and now i only have one row of LED's lighting up at all (top right)..... :getlost: with the 74HC595 by adjacent do you mean side by side or opposite each other? (IC's in or out?) also what would be the best way to test the LEDs for shorts? thanks Quote Link to comment Share on other sites More sharing options...
Wilba Posted August 24, 2010 Report Share Posted August 24, 2010 OK... if you did all the checks in post and so SO and SI are definitely NOT conected... then I guess the problem with LEDs is somewhere near the two 74HC595. I hope. By "adjacent" pins, I mean, pins next to each other, where a blob of solder might bridge between them. There are really only two things that can go wrong with soldering - a bad solder joint (i.e. no connection between track and component pin) and a short (i.e. a connection to another pad). You need to check for both, in the area of the two 74HC595. Look at the attachment... see how the RC, SC and SO tracks connect from J1 to IC3, IC4. RC and SC also connect to J2. SO is conected to IC3 pin 14 and "shifts bits" into IC3. Similarly, IC3 pin 9 is the output, and is connected to IC4 pin 14 and thus "shifts bits" into IC4. You can take out IC3 and IC4 and test if the LED matrix is connected properly. To do this, you would "ground" one row of LEDs by grounding one of IC3 pin 2,3,4,5,6,7 (where track leads to a "common cathode" LED row). Then apply 5V to one of IC4 pin 15,1,2,3,4,5,6,7 (where track leads to R1-R8 and to a "common anode" LED column) Note it's actually two physical columns of three LEDs... it's mirrored either side of the gap in the middle. You can take your 5V/ground from pin 15 and 8 (note thicker track for 5V, pad connected to bottom layer ground plane). Be careful not to stick things thicker than an IC pin into the sockets... cut resistor leads are OK. Testing your LEDs is a good start, because then you know it's something wrong with IC3,IC4 or the connections to that. OK... so, assuming you tested LEDs OK... then check for shorts/bad joints in IC3,IC4. Maybe something is wrong with SO->IC3:14 or IC3:9->IC4:14 or SC->IC3:11->IC4:11 or RC->IC3:12->IC4:12 or any of the other pins... it can only take one bad joint to make something not work properly (like the grounded pin 13). Keep at it... as a last resort, you can send it back to me for fixing (offer exclusive to Aussies who try hard to fix things themselves) :DSammich CS.pdf Quote Link to comment Share on other sites More sharing options...
radiotron Posted August 31, 2010 Author Report Share Posted August 31, 2010 ok wilba doing the first test i can't get the LED's lit i can't find the problem with the LED's (how do i test this to find the culprit) all the voltages are fine on the CS pin 13 on both IC sockets is grounded the resistors are resisting! GF is getting tired of my shit on the kitchen table :wink: Quote Link to comment Share on other sites More sharing options...
Wilba Posted August 31, 2010 Report Share Posted August 31, 2010 You should check again that you're following the instructions correctly. It makes no sense that you had some LEDs light up via the test firmware, but now can't make them light manually. So... you say the voltage tests are good... you SHOULD be able to light at least some of the LEDs this way. If you still can't, test for continuity between the IC socket pins and the LED leads they connect to. Refer to the PDF. Quote Link to comment Share on other sites More sharing options...
radiotron Posted August 31, 2010 Author Report Share Posted August 31, 2010 ok to check i'm doing the testing right how are the pins numbered on IC3/4 ? Quote Link to comment Share on other sites More sharing options...
nILS Posted August 31, 2010 Report Share Posted August 31, 2010 Like they are on any DIP IC. Quote Link to comment Share on other sites More sharing options...
radiotron Posted September 1, 2010 Author Report Share Posted September 1, 2010 You can take out IC3 and IC4 and test if the LED matrix is connected properly. To do this, you would "ground" one row of LEDs by grounding one of IC3 pin 2,3,4,5,6,7 (where track leads to a "common cathode" LED row). Then apply 5V to one of IC4 pin 15,1,2,3,4,5,6,7 (where track leads to R1-R8 and to a "common anode" LED column) Note it's actually two physical columns of three LEDs... it's mirrored either side of the gap in the middle. You can take your 5V/ground from pin 15 and 8 On IC3 or IC4? Just to make sure i'm testing this right(note thicker track for 5V, pad connected to bottom layer ground plane). Be careful not to stick things thicker than an IC pin into the sockets... cut resistor leads are OK. so i've soldered resistor legs to the ends of two cables to make test jumpers to go between the points am i doing this right? thanks for the pic Nils that was how i was counting Quote Link to comment Share on other sites More sharing options...
Wilba Posted September 1, 2010 Report Share Posted September 1, 2010 wtf... did I write pin 15? I meant pin 16. Both IC3 and IC4 have 5V on pin 16 and ground on pin 8. Refer to the voltage tests page of the build guide. I am referring to the exact same pins which are labelled with coloured dots for testing the voltage (5V or Ground). FYI nearly all "logic" ICs have identical Vdd/Vss (5V/ground) pins... top-right and bottom-left (where pin 1 is top-left). This is also why the 8 outputs of a 74HC595 aren't all on one side (i.e. pin 1-8). Quote Link to comment Share on other sites More sharing options...
radiotron Posted September 1, 2010 Author Report Share Posted September 1, 2010 wtf... did I write pin 15? I meant pin 16. Both IC3 and IC4 have 5V on pin 16 and ground on pin 8. Refer to the voltage tests page of the build guide. I am referring to the exact same pins which are labelled with coloured dots for testing the voltage (5V or Ground). FYI nearly all "logic" ICs have identical Vdd/Vss (5V/ground) pins... top-right and bottom-left (where pin 1 is top-left). This is also why the 8 outputs of a 74HC595 aren't all on one side (i.e. pin 1-8). ok that makes a bit more sense! so how are the LEDs supposed to light up (in rows i assume?) i'm getting one LED to light up at a time and i can move the one LED around XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX these LEDs won't light up hopefully you can help me narrow this down some more sorry i'm so crap at following circuits! Quote Link to comment Share on other sites More sharing options...
radiotron Posted September 1, 2010 Author Report Share Posted September 1, 2010 wtf... did I write pin 15? I meant pin 16. Both IC3 and IC4 have 5V on pin 16 and ground on pin 8. Refer to the voltage tests page of the build guide. I am referring to the exact same pins which are labelled with coloured dots for testing the voltage (5V or Ground). FYI nearly all "logic" ICs have identical Vdd/Vss (5V/ground) pins... top-right and bottom-left (where pin 1 is top-left). This is also why the 8 outputs of a 74HC595 aren't all on one side (i.e. pin 1-8). ok that makes a bit more sense! so how are the LEDs supposed to light up (in rows i assume?) i'm getting one LED to light up at a time and i can move the one LED around XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX XXXXXXXX these LEDs won't light up hopefully you can help me narrow this down some more sorry i'm so crap at following circuits! Quote Link to comment Share on other sites More sharing options...
Wilba Posted September 1, 2010 Report Share Posted September 1, 2010 This is good news, perhaps. Look at the PDF I attached. Those LEDs have one thing in common - their "anodes" are all connected to R1, then R1 is connected to pin 15 (yes, pin 15 I am sure!) of IC4. So first, check you are really testing pin 15. Then check the pads of R1 and IC4 pin 15. Check continuity between IC4 pin 15 and the upper pin of R1, then between the lower pin of R1 and the anodes (left) pins of those six LEDs. Quote Link to comment Share on other sites More sharing options...
radiotron Posted September 2, 2010 Author Report Share Posted September 2, 2010 HOLY SHIT IT'S ALIVE!! the problem was so stupid :pinch: :blush: i had a 74HC165 in either IC3/4 depending on how i put them back in without looking!!! (i think the non soldered S 12 was the first problem then not looking when i put the IC's back in f**ked me up!) anyway it's working and sounds AWESOME! thanks wilba and nils for answering my dumb Q's! Quote Link to comment Share on other sites More sharing options...
Wilba Posted September 2, 2010 Report Share Posted September 2, 2010 Quote Link to comment Share on other sites More sharing options...
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