+karri Posted June 12, 2015 Author Share Posted June 12, 2015 Yes. We might even use the same package and decide later which eeprom to solder in. Quote Link to comment Share on other sites More sharing options...
aminor00 Posted June 17, 2015 Share Posted June 17, 2015 This sounds very exciting and I would like to help. If you need extra orders to make up a batch then please put me down for 2 Cards and 1 Programmer. Quote Link to comment Share on other sites More sharing options...
+karri Posted June 17, 2015 Author Share Posted June 17, 2015 (edited) I just sent in the updated batch to Tinysine. Here is a picture of the design. Note: much longer pads for the cart now The 65k EEPROM uses one extra byte for addressing so all transfers are slightly slower than the 2k chip. Edited June 17, 2015 by karri 1 Quote Link to comment Share on other sites More sharing options...
GadgetUK Posted June 19, 2015 Share Posted June 19, 2015 Sorry I didn't see all the updates on this thread until just now. I presume you've sorted the issues? My programmer does seem to support the chips you are using - tbh that's the way I planned on using the carts as I've not got a Pi yet. Quote Link to comment Share on other sites More sharing options...
aminor00 Posted June 23, 2015 Share Posted June 23, 2015 Karri, I've changed my mind. Please can you put me down for 5 Cards and 1 Programmer please? Thank you. Quote Link to comment Share on other sites More sharing options...
+karri Posted June 24, 2015 Author Share Posted June 24, 2015 Karri, I've changed my mind. Please can you put me down for 5 Cards and 1 Programmer please? Thank you. Ok. -- Karri Quote Link to comment Share on other sites More sharing options...
aminor00 Posted July 10, 2015 Share Posted July 10, 2015 (edited) Thanks for the info Karri, I'll try those programs out. I got the quote back for 10 pieces it was £136!!!!!! I might be able to get a cheap flight to Finland for less! I'll keep searching....... Rgds BadPricey Sorry to resurrect a very early post about 3D printing the cart cases. I've been looking into this in the UK too. There's a company here: http://www.3dprint-uk.co.uk/the-basic-rules-for-stl-files/ They offer very helpful tips on 3D printing things, just click the "Tutorials" menu at the top of their page. Start with the link I've added above and work through the advice. The best advice is to use "sprues" to connect each part as it brings the cost down in many cases. There is advice on using a 1mm minimum thickness for the walls and they offer a free polishing facility to make the printed items look great. A lot of their advice may only apply to their pricing structure, their type of 3D printer or the plastic type they use but it's worth reading and they seem to be cheaper than £136 for 10 pieces! I've tried Blender and just can't get used to it. It has a learning curve like the White Cliffs of Dover! 3DS Max 4 was so easy back in the day but wasn't/isn't free of course. Edited July 10, 2015 by aminor00 Quote Link to comment Share on other sites More sharing options...
+karri Posted July 10, 2015 Author Share Posted July 10, 2015 Hi amonor00, I managed to tame Blender and have no problems with knowing how to optimize 3D printing anymore. For Lynx carts it is actually best to print them standing up and not lying flat. Today I received the final pcb carts and during the weekend I plan to test them out. My vacations start now. If the weather is as rainy as it appears to be now I can easily spend a day at the library and print out a dozed of cart covers. For free!!! I would like to emboss a glass of Martini on the 3D cart cover or perhaps a gun instead of the text LYNX. This is for "Shaken, not stirred" of course. 1 Quote Link to comment Share on other sites More sharing options...
+karri Posted July 16, 2015 Author Share Posted July 16, 2015 Yesterday I managed to program 64k of the cart. After that the programmer refused to program anything. Obviously there is still some bug in my code Quote Link to comment Share on other sites More sharing options...
+karri Posted July 18, 2015 Author Share Posted July 18, 2015 (edited) The software bugs are now sorted out and the cart works as it should. What does not work is the 3D cover. It did not fit perfectly. So it is time to re-design the stl file. The poll in another thread shown a clear sign that cost is no issue. The 65536 byte eeprom seems to be a winner. I try to order a few chips today to test them out. So it looks that this mini-kickstarter will contain the cart equipped with a 65535 byte eeprom and a 512k flash. A cool combination imho. Edit: I just ordered 10 chips from UK. (AT24C512C-SSHD-B, EEPROM Memory 512kbit,, 65536 x, 8bit, Serial-2 Wire, 550ns 2.5 → 5.5 V, 8-Pin SOIC). They had them in stock. The actual price was 1.38€ so a bit cheaper than me assumption of 2€. This chip has a few operating modes. Write a byte = 16-bit adress plus data byte Write up to N bytes = 16-bit address plus bytes (only the low address byte increments so you need a little intelligence here). Unfortunately N depends on the manufacturer. It can be 16 - 128. Dummy write = 16-bit address Read next byte = data byte Read many bytes = data bytes (just read as many as you want) So what should the API look like? unsigned short eeseek(unsigned short pos); unsigned short eewrite(unsigned char *buf, unsigned short size); unsigned short eeread(unsigned char *buf, unsigned short size); or void eeput(unsigned short addr, unsigned char byte); unsigned char eeget(unsigned short addr); Edited July 18, 2015 by karri Quote Link to comment Share on other sites More sharing options...
LX.NET Posted July 18, 2015 Share Posted July 18, 2015 Great news Karri. As for the API, why not both. The latter could be a higher level abstraction of the former (and using it internally). That would give a choice for the dev. Quote Link to comment Share on other sites More sharing options...
GadgetUK Posted July 18, 2015 Share Posted July 18, 2015 Thanks for the update =) Quote Link to comment Share on other sites More sharing options...
+karri Posted July 18, 2015 Author Share Posted July 18, 2015 (edited) Hi guys, I know I am changing things around too much... The 2k chip is dropped from the design. As there was a bit space I put in a 93C86 (or 66, 46). This is to allow me to create some old carts I done in the past as well. Solitaire, Mega Pak I, Lynx Reloaded comes to mind. Another thing was how to clock the EEPROM chip. The old designs needed a separate CS and CLK. In the new 2-wire chip we could actually simplify things even further. So instead of wasting A17 for CLK I changed it to use A1 just as in the old EEPROM design. The benefit here is that all the block select pins are now unused (A11 - A18). Or lets say that using the A11-A18 pins should not affect the eeprom. In the current design there was a potential clash that bothered me. Fortunately I need to cut just one trace and add one wire to test this in the current design. So no new pcb's are required. The factory It takes only USB power as input. The control is through the WiFi dongle. Raspberry Pi acts as a WiFi server at 192.168.42.1 so you can just log in with your laptop to burn carts. The cable between the laptop and the Raspberry Pi is just to give 5V to the burner. I already tried a 128k game (Blue Lightning), a 256k game (Lemmings) and a 512k game (Ninja Gaiden III). All worked ok. The cart also fits my Lynx perfectly. It also fits into Lynx I giving plenty of space to close the door. And it works as well. Easy to remove also thanks to Duraniks design. Edited July 18, 2015 by karri 4 Quote Link to comment Share on other sites More sharing options...
BadPricey Posted July 18, 2015 Share Posted July 18, 2015 I'm speechless karri. What a wonderful job you have done. So impressive, I love the "Lightly Modified" Lynx, signed as well Well done Rgds BadPricey Quote Link to comment Share on other sites More sharing options...
+karri Posted August 4, 2015 Author Share Posted August 4, 2015 Here is the final cart cover. The new chips 512k flash plus 64k eeprom (or old eeprom) fit in here. The 4 pins fit into the holes on the PCB. Helps positioning the cover a lot and also gives mechanical support for pulling the cart out of the Lynx. cover2.stl.zip 4 Quote Link to comment Share on other sites More sharing options...
Turbo Laser Lynx Posted August 13, 2015 Share Posted August 13, 2015 Great photos. The Burner and everything looks great, can't wait to test it out myself! Nice having your Lynx autographed by R.J.Mical ^o^ Quote Link to comment Share on other sites More sharing options...
+karri Posted August 14, 2015 Author Share Posted August 14, 2015 Working on the fourth connector version... The top right is copper wire around elastic rubber. Too hard. Not elastic enough. Top left is braided wire around elastic rubber. Not enough movement. Bottom right is the Lynx Connector. Works great. Bottom left is safety pins. These should have enough movement and the spring is pretty good. I just need to make some 3d plastic guides in the library on Monday. I hope this works as it should. Above is a closeup of the braided wire one. A friend of mine called and asked if I want to go sailing. So I sneaked out of the office at noon and came back in the evening. The Lynx can wait... 2 Quote Link to comment Share on other sites More sharing options...
+karri Posted August 16, 2015 Author Share Posted August 16, 2015 Status update. I wrote some factory tests to check the carts before shipping. But as usually got stuck. The 64k eeprom stubbornly refuses to co-operate. The ACK bit is correctly received after the 1st control word. But no ACK bit after the high-address byte. Time to start reading datasheets ... again. The device has correct markings. Works from DC up to 1MHz speeds. Voltage range 2.5V to 5.5V. Operating temperature -40°C to +85°C. Endurance: 1,000,000 Write Cycles. Data Retention: 40 Years. Looks good. Works bad. A random read should take 38us at max speed. A random write takes 5ms. So writing the entire memory is 6 minutes. Making a screen dump would take 41 seconds. This is good to keep in mind when planning what you can use this chip for. Quote Link to comment Share on other sites More sharing options...
GroovyBee Posted August 16, 2015 Share Posted August 16, 2015 Status update. I wrote some factory tests to check the carts before shipping. But as usually got stuck. The 64k eeprom stubbornly refuses to co-operate. The ACK bit is correctly received after the 1st control word. But no ACK bit after the high-address byte. Time to start reading datasheets ... again. What value pull-up resistor have you got on SDA? Quote Link to comment Share on other sites More sharing options...
+karri Posted August 16, 2015 Author Share Posted August 16, 2015 (edited) At the factory tests I use internal pullup on Raspberry Pi 2. It appears to work ok as a byte read produces 0xff all the time. Plus the first control byte gets ACK at LOW as it should and after that all bytes produce ACK HIGH which is an error indicator. Edited August 16, 2015 by karri Quote Link to comment Share on other sites More sharing options...
GroovyBee Posted August 16, 2015 Share Posted August 16, 2015 At the factory tests I use internal pullup on Raspberry Pi 2. It appears to work ok as a byte read produces 0xff all the time. They'll be quite weak and more than 50K. I'd suggest something like 1k6 (to 4k7) on the PCB. Quote Link to comment Share on other sites More sharing options...
+karri Posted August 16, 2015 Author Share Posted August 16, 2015 (edited) Ok. I will try that. The good thing is that we can still change the final PCB and add space for a SMD resistor. Just checked the datasheet. They are talking about 1k3 pullup. Thanks for the comment. This may be the reason. What about the real Lynx AUDIN pin? It did not need a pullup I think. Perhaps I add it on the programmer board and not the Lynx cart? Edited August 16, 2015 by karri Quote Link to comment Share on other sites More sharing options...
GroovyBee Posted August 16, 2015 Share Posted August 16, 2015 Just checked the datasheet. They are talking about 1k3 pullup. What supply Vcc is that for? What about the real Lynx AUDIN pin? It did not need a pullup I think. Perhaps I add it on the programmer board and not the Lynx cart? What is on the Lynx schematic? How are you driving SDA? Are you simulating an open drain drive stage? By that I mean to make the pin high you make SDA an input (at the programmer/Lynx side) and rely on the pull-up to make the line high. When you want SDA to be low (from the programmer/Lynx), make the pin an output and drive it low. Quote Link to comment Share on other sites More sharing options...
GroovyBee Posted August 16, 2015 Share Posted August 16, 2015 Just checked and AUDIN has a 10K pull-up. Quote Link to comment Share on other sites More sharing options...
GroovyBee Posted August 16, 2015 Share Posted August 16, 2015 If you don't have a scope get one of these Saleae compatible USB 8 channel logic analysers :- eBay Auction -- Item Number: 221836175483 Its cheap and they can do I2C packet forming e.g. decode SCL/SDA signals into something that is human readable. They aren't as good as more expensive logic analysers but you'll probably get some good use out of it. Quote Link to comment Share on other sites More sharing options...
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