192: Sunday 22nd March

I have been trying to get the display working properly and decided to mount the capacitors on the display connector board using the solder pads provided. The picture below shows the back of the board with the connections made to the display connector from the solder pads. This is not my finest bit of soldering, but the connections are good.

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The next picture shows the top of the board with the capacitors mounted. I tried the display again, and it is still not working. I am not getting the LCD voltage to drive the display. Injecting the voltage shows the blue rectangle again, but when it was aligned to the correct voltage it was all black and you could see the dots being displayed, but that was all. I suspect the capacitors may be at fault as I ran all the codes suggested by the supplier and still the LCD voltage was not right, it was reading 0.16v and should have been -4v to ground. I have now ordered some surface mount capacitors and I shall mount them when I get them. I hope that works as I am not sure what else I can do now.

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The picture below shows the plate for the controls and display to go into the centre console. I figured I would cut the rectangle for the display and then give a coat of gloss paint. I used the displayed rectangle to measure the actual display and then cut the rectangle with a hammer and chisel. The plate was so thin that any extensive filing or sawing would have distorted it dramatically. Chiselling was the best option and after I had made the first cut, I touched it up with a file to smooth the cuts out and get rid of burrs. I checked it with the display and made some minor adjustments with a file. I am not exactly sure how I am going to secure the display. I shall probably glue some spring clips to the back that the display can slide into.

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I applied gloss black paint and allowed it to dry for a while. When the paint was still tacky I applied the graphics that I had printed off. The Forward, Reverse and PAS were made with a tape printer. I made these some time ago when I made the original panel. A quick coat of clear over the top of it all then it is ready to mount the switches etc. and fix it all back in the car. I shall come back to the display when I have it working as there is a lot to do even once I have some basic information showing on the display. The batteries will be monitored by two eight channel A to D converters through linear opto-couplers. The A to D converters shall be linked to a PIC chip through a serial port and the PIC chip will also handle the display of the levels on the screen.

191: Thursday 19th May 2011

I keep forgetting to mention that I got a write up in the Revenge of the Electric Car, click to go there. That was a bit random, but it came about because of a comment that I left there and I was contacted by email. I had a conversation on the phone with the graphic display supplier Technical Director who turns out to be a real keen electronics person and knows all about the display. He had emailed me to show that my display was working after I sent it back for testing. I need to pick it up from the post office now as he has sent it back. I am pleased to know it is working and I also noticed in the photo that I had bought the wrong display type and that the circuit that he had the display connected to had the DC-DC converter LCD voltage capacitors mounted. We discussed this and the board that I got from Newhaven displays has some solder pads that happen to be just right for mounting the capacitors, so I did this last night and this then gets them off the prototype board and closer to the display itself. Hopefully I can get this working now. I shall post some photos of the capacitors mounted on the board soon.

This display is a reflective type and I was expecting an illuminated type, white on a blue background. I can use this for testing and then just swap it out for the white on blue display when I get one. They do have the same connections, but they also have an LED back light that just needs some power. This photo shows my actual display, so I know it works now and I can set about improving my test set up.

190: Sunday 15th May 2011

Yesterday I spent the day with my friend working on his car, but I took the opportunity while I was there to grab a piece of aluminium sheet and knock up the panel for the centre console. I then went on to fix an MiG welder he had that was not working how he wanted. The MiG wire would stay live when you were not feeding, and he wanted it to switch off the welding current when the feed trigger is released. So I obliged, but it did take a lot longer than I expected. So onto Sunday and the upgrades begin. First I removed the gear lever. For this I had to jack up the car and put stands under it, then remove the bolts from the gear selector rod and the support rod at the gearbox end, then back inside the car to undo the four bolts holding the gear lever. This then dropped down onto an old heat shield (another old surplus part that I need to remove at some point) and with a bit of jiggling I pushed it forward and then it dropped down. The photo below shows the complete gear lever removed. While I was underneath I went searching for a rattle that I was getting for the back end of the gear box. This normally occurred when releasing the throttle pedal and the Regen braking drag slows the car. I found that the rear gear box mount had all three bolts loose. This was not coincidence, I must have done them up hand tight and forgot to finish them off when I mounted the gearbox. Otherwise they have worked loose. Either way, they are tight now and I should not hear that rattle again.

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I took the panel that I had made on Saturday and applied it to the console. There were 2 main problems to start with. Firstly the cut-outs for the screws needed some filing as the panel would not go on and secondly I had put the curve in the plate the wrong way, so I needed to un-curve it and curve it the other way. I then went about removing the old panel from the upright part of the centre console. While I was doing this I realised I had the Zapi motor controller programmer unit hanging on to Tom Tom bracket on the vent flaps with cable ties for some time now. The unit had warranty void if removed stickers on the side, but I figured it must be beyond warranty now anyway, so I broke the seal and found that the circuit inside sits on spacers. This meant that there was a void underneath the circuit board, so running a couple of screws through the case to fix a mounting bracket to the back of the case was not going to be a problem. I took a strip of 3mm aluminium bar and fashioned a bracket that slipped under the edge of the centre console face plate with no screws showing. After many adjustments I fixed the bracket to the back panel of the unit and gave it a quick spray of Matt black paint so the bracket would be hidden. While the paint was drying I made some elbow clip to clamp the plate from the screw fixing holes to the new plate for the lower centre console. They did clash with the fixing points for the console itself so I had to rework them a few times. When I fitted all together I found the new plate was clashing with the upright centre console, so I needed to trim it to prevent this. I had a pair of aviation shears for trimming sheet metal, so I dug them out, tightened up all the joints and give them a go. To my dismay they just came apart and bent the metal rather than shearing it. They are now consigned to the scrap bin and I took out my hack saw and started hacking. After much tapping and banging I eventually got the sheet back to the same shape as before and offered up the controls to check the layout I had drawn. I preferred to have the PAS and emergency stop button swapped giving more separation between the forward reverse switch and the emergency stop button.. I used the old plate as a template and marked the new plate with a pencil. I used a spade drill to make the holes as I did not have any 22mm twist drills. I know this was meant for wood, but the aluminium was so soft and thin that the spade drill had no trouble cutting it. The PAS switch needed a 12mm hole and I had a drill for that. A quick touch-up with a file and the holes were done and the plate was read for painting. I keyed the surface with some sandpaper, but the first rub over was a little bit too course, so the first coat of paint had lines in it. I gave it a light rub over with some fine paper and another coat of paint and hopefully it will dry a lot better. I then went back to the Zapi programmer and mounted this in the car. It looks so much better now and I can get to my radio and mount my Tom Tom again. The photo below shows after the first coat with 2 of the controls loose fitted. I have since repainted it and hopefully I can start on the graphics to stick on before the  clear coat goes on. I might need to use a gloss paint instead if the coverage does not improve as this tends to be slightly thicker and cover marks better.

189: Friday 13th May 2011

Today my batteries went back to the supplier for a part refund, so now the Probatron is off the road until I get some more batteries. Now I can work on upgrades to the car and fixing some of those niggling problems that I keep putting off. If I have time I may even take off the bumpers and clean up the rusty bits underneath. I have had the Probatron in 3rd gear now for about 4 months and never had the need to change gear at all. For my motor and controller and gearbox, third gear is fine. So I have decided to remove the gear lever, make up a panel for where the gear lever was and mount some of the controls in this new panel. It will make for easier access to the forward / reverse switch and also it gives me somewhere to mount the new display that I am still working on. The picture below shows a mock up of the graphics that I will have on the panel. This also shows roughly where the forward / reverse switch, emergency stop button and PAS switch would be mounted and also the display.

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The next picture shows the back of the centre console with the gear lever gaiter still in place. This has a plastic flange that screws on in four places, so this means there are four fixings ready to go. I took this off and removed the gaiter from the flange. I could cut the flange, but it will be just as easy to make some bent aluminium strip to fix the new panel on the back of the console.

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The next picture shows the centre console removed with the gear lever gaiter still in place. This is where the new panel will go.

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The next picture shows the centre console with the mock up mounted behind. I used some cardboard to support this and just taped it on the back side. This was just to check the positions of everything, check the angles and just get a feel for how it will ultimately look. The graphics will be white on a black background.

188: Wednesday 4th May 2011

I haven't mentioned much about batteries recently as I have been discussing this with my supplier. They had them for testing for 3 weeks and confirmed they were just about cycled out. I had them back and I have been getting about 7 miles before slowing down where I was getting around 40 miles when they were new. They have offered to buy them back for half the money I paid. Since the warranty was for 1 year and I have had over 8 months use, I have accepted this, so next week they will go back and I will get the cheque. I am not going back to Lead Acid batteries unless some recycled ones come along real cheap like the first set I had. I have some money coming in soon and hopefully I can drum up enough to get lithium batteries. I have decided to buy the batteries in stages and I shall start with 60Ah and 128v. This is 40 batteries in a string. I shall add another string of the same batteries at a later date when I have saved some more money. I realize this is not ideal, but it is what my budget allows for.
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On the display subject, I have tried the test process recommended by the display supplier and it is just the same. I believe the display is damaged and I need another to verify this. Hopefully I can send this one back and the supplier can test it.

187: Monday 25th April 2011

Today I decided to get the display control simplified so it was easy to trigger events from data sent to the graphic display. In order to do this I needed a development environment. Fortunately the usb interface came with a demo program as a stand alone program, but also as source code in various programming languages. I opted for visual basic in the vb.net domain as there was a vb2008 source code version of the demo already coded. First I had to download the Microsoft dot net framework. That took a while. Then I downloaded visual basic express 2010 from Microsoft. This is free, cool. Once I had done the installations and restarted my PC, I loaded the solution file and there I could edit the source code. This was great as the vb graphic interface development is really easy. So I dragged the bottom of the form down to make it bigger, added buttons for 'Reset', 'LCD on', 'LCD off', 'All points on', and 'All points off'. I also added a 'Toggle data' button this was so I could enable the data set in the check boxes for the digital outputs. I added a timer and set this to 1 second initially and set this to bring on the analogue voltage at the full 5v, then back to 0v after the timer had expired. This was connected to the 'E' terminal on the display to enable the data on the bus. So each button would set up the digital outputs, then bring on the analogue output for a time. I could see this working just fine, so I then set the timer to 10 milli seconds. On the board you can still see a short blip when the analogue output comes on and goes off again. I am using this just like a digital signal really, but I only had 8 digital outputs and they are used for D0..D7 input of the display. This made it very easy to send commands to the display. I installed a simple mechanical button on the prototype board to supply the hard reset voltage when pushed, so I could stop the display from locking me out. I could still only control the display to bring it on and off. I am not sure why this is right now, but I suspect the display is damaged at this point in time. I am not getting the LCD voltage from its on-board DC-DC converter, so I had to supply this using my split rail supply. I get the blue background, but no white dots. I tried the volume control, power control and resistance ratio settings amongst others as well as sending the data to the ram and nothing, nada. I shall wait till pay day and order another display and hopefully that will work. I shall also try contacting the manufacturer and getting them to supply me with a start sequence for the display and some tests to try out. I have the display data sheets (see link in side bar) for the display and the chip set on the display assembly. I have tried the sequence I believe is recommended by Epson and it does not work. This is disappointing, but nothing has been simple so far, and in the typical tradition of this whole project I have typically had 2 of everything, except the Zivan charger and Zapi controller that have worked faultlessly since the day I first tried them.

186: Sunday 24th April 2011

Started off by rewiring the usb interface as the outputs were for open collector transistor drivers and only 0.6v. There was a 5v output to each of the LEDs, so I soldered a connection to a terminal strip with screw terminals. I used a double sided sticky pad to mount this on top of the chips. I then made up a simple ribbon cable with 9 connections, one for each of the 8 outputs from the usb interface and one for ground. This had a strip of pins on the other end so I could plug it into the prototype board. I then figured out which of the bits I need to change to send a 'display on' and 'all points on' messages. The rest of the bits were wired directly high or low. I know this is really crude, but it is just to get the display up and running. I cleared up the desk with my computer on it and moved my prototype board and the display etc. over there with the usb interface. You can see this in the photo below.
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After a thorough read of the data sheets, I found a couple of minor issues, but there was a voltage converter inside the chip that was supposed to generate a large negative voltage supply for the display. This was not working and I had the capacitors the wrong way round at one point as the two data sheet showed different polarities. I trust the Epson chip spec sheet as this is the source document. I could not get the display circuit to produce the voltage so I consulted the notes on how to connect an external voltage. I have a split rail supply on the prototype board as well as a separate 5v supply and the positive and negative rails are separately adjustable. I linked the 5v supply ground and the split rail supply ground so they had the same reference. The input voltage needed to be -9v with respect to the positive 5v supply, net effect is -4v with respect to ground. I set the negative rail to -4v and the display flicked on when I powered up. This was progress. I could see like a grid when I sent the command to switch the display on and then another very slight change when I sent the instruction to switch all points on. When I then sent the command to switch the display off, it went right off. I had to use a wired reset low to get the display back, or switch off the power supply. In the photo below you can see the display with a blue square in it. I tried sending some data and it didn't make any difference, but I had to go for dinner and finish up for the day. I have a feeling there is something else I need to do to select the right brightness level or something as I was expecting all the dots to illuminate with the 'all points on' request. I have made progress as the display is visibly responding to my requests. Step by step I will get there. I did a bit of a rewire and I shall use 2 analogue outputs from the usb interface and the 8 outputs exactly as the eight bits for the data. I only need to control the enable signal and the data or control line (A0) that are now connect to analogue outputs. I shall switch these directly from min to max to go from 0v to 5v, so they are just like the digital signals. If anybody has ideas why I am not getting any dots lit up, I'd appreciate your help.

185: Saturday 23rd April 2011

Started work on the graphic display today. First objective was to get the display powered up and basically showing something that I have decided on. I now had the connector board from Tim in USA, cheers buddy. Had a collection of pin strips from when I was making the other displays. In the photo below you can see after I have added one row of pins to the board.
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In this photo you see the second row of pins added. This layout is identical to IDE connectors for a floppy disk drive and I had a couple of spare ribbon cables with connectors, so that was a bonus.

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In this photo you can see the ribbon cable connected.

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In this photo you can see how I handled the other end of the ribbon cable that needed to connect to my prototype board. This shows one of the rows of pins that would connect to the IDE connector on the other end of the cable. As there are two rows then I needed to make two of these and offset the pins to bridge the gap on the prototype board.

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In this photo you can see the two connectors I made between the IDE cable connector and my prototype board. I cut the cable as the next part went to a different connector and it made it easier to handle.

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In the next photo you can see everything connected. The bits on the left of the prototype board were from another project some time ago. The display is connected to the adapter board and I put a double-sided sticky pad on it's back to stick it to the ribbon cable temporarily. This was for support as the display's own ribbon cable is like a tape. I tried just hooking up the 5v supply, and then adding the other components that were shown in the example circuit on the data sheet. I tried manually wiring the circuit data lines to send some simple instructions, but there was nothing on the display. I still need to add capacitors for the LCD driver circuits and I did not have the right values. I had the right capacitors and resistors for the voltage inputs and have added these already. I need to check what I ordered for this project and see if I should have these parts. Other wise I need to go buy them. I want to finish this up before I try anything else. I decided to just send a control instruction to turn all points on initially. That will prove that the display works. I have a usb controlled interface that I can use to set up a simple bus and send data from a PC to progress from there, then I can work out how to get a PIC chip to do the same job of the usb interface. I was impressed with the Velleman website as I bought the board about ten years ago and I have now misplaced the disk that came with it. I went to the website and within minutes I had downloaded a complete suite of example programs in many different computer languages and instructions on how to install the drivers etc. Another couple of minutes and I had the interface up and running. I now need to clear some space on the bench where my PC is and move the prototype board over to it as I don't want to trail a long usb cable across and then have to keep going backwards and forwards to see what has worked or not.

184: Sunday 10th April 2011

I have had some dialogue with Tim Catellier recently and he has received a connector for me and posted it on as the company wanted $130 to ship it to UK for a $10 part. With this connector I can start the development of my graphic display. I have now had my local supplier send me the wrong connector 3 times and I have asked for a refund. This is my back-up plan and right now I am just waiting for the connector to arrive. It is a 30 way ribbon connector breakout board. This will enable me to access the very fine connections from the ribbon cable to the graphic display. It is a simple circuit board with connection spaced apart so they are easy to solder onto. I shall then connect another bigger ribbon cable to this and then to my prototype board. I can then connect up 9 or 10 switches to manually sequence through the graphic locations on the screen and program them one-at-a-time to generate the static display, then I can start coding up a PIC chip to do the same. Replacing the switches with a PIC chip shall make it possible to run the display and generate the graphics, then onto the measuring circuits. There is a load of mini projects involved in getting this display working, so I hope it will make interesting reading.

183: Friday 1st April 2011

I got my car back on the road today. Still discussing the capacity issue with my batteries, but the supplier has tested them and now they are back on the car. I am still limited to 10 miles, but this is enough to get me to work on a cold day, just. When I was fitting the batteries back I found a broken weld on the battery trays and this was causing that annoying banging noise. I drilled through and bolted it back together and I shall get round to re-welding at some point soon. I cured the vibration on the rear centre stop lamp and and fixed my rear view mirror back on the windscreen and all is back up ready to go. I now have the charger set to provide a float charge after the normal charging cycle to keep it topped up to a good level so long is the cord is connected. This means I don't lose charge while it is sitting after the charge cycle completes, cool. Seems to have the desired effect. Anyway the car is truly silent now, no knocks or bangs any more.