Madhatter1 Posted February 11, 2021 Share Posted February 11, 2021 This is similar to a CF7, but use SD card and has nothing to do with CF7. It allows a TI-99/4a to use disk image volumes on SD card as floppies. I started this a couple years ago and have decided to share it in case someone else wants to build one. https://github.com/dennishatton/TI-99-4a_SD_Disk_Project 16 3 Quote Link to comment Share on other sites More sharing options...
Shift838 Posted February 11, 2021 Share Posted February 11, 2021 nice. i may have to order a few PCBs from my supplier during my next round. if anyone want's to get on board with a PCB shoot me an email. 1 Quote Link to comment Share on other sites More sharing options...
AtariNostalgia Posted February 11, 2021 Share Posted February 11, 2021 What's the estimated price on these? Quote Link to comment Share on other sites More sharing options...
Shift838 Posted February 11, 2021 Share Posted February 11, 2021 3 hours ago, Madhatter1 said: This is similar to a CF7, but use SD card and has nothing to do with CF7. It allows a TI-99/4a to use disk image volumes on SD card as floppies. I started this a couple years ago and have decided to share it in case someone else wants to build one. https://github.com/dennishatton/TI-99-4a_SD_Disk_Project Very cool project. I checked out the Kicad project and there does not seem to be a created PCB file (just a blank one). Did you ever get one tooled or have gerbers for the is project already? Quote Link to comment Share on other sites More sharing options...
Madhatter1 Posted February 11, 2021 Author Share Posted February 11, 2021 1 hour ago, Shift838 said: Very cool project. I checked out the Kicad project and there does not seem to be a created PCB file (just a blank one). Did you ever get one tooled or have gerbers for the is project already? There is no PCB and I don't intend to make one. I built this using wire wrap for myself. I never know when I will make a change. If someone wants a PCB, They can use KICAD to make one. I wished I would have used Eagle, Because Eagle is now part of Fusion 360. In which case I could have milled a PCB on my CNC. This ATMEGA162 emulates the disk controller and interfaces to the TI DSR rom. 1 Quote Link to comment Share on other sites More sharing options...
fabrice montupet Posted February 11, 2021 Share Posted February 11, 2021 I like your project and I think that I will make make one , thank you ? 4 Quote Link to comment Share on other sites More sharing options...
Shift838 Posted February 11, 2021 Share Posted February 11, 2021 53 minutes ago, fabrice montupet said: I like your project and I think that I will make make one , thank you ? i think i will use the schematic to port it over to eagle then. 1 Quote Link to comment Share on other sites More sharing options...
RickyDean Posted February 12, 2021 Share Posted February 12, 2021 I've got two Bunyan and two Fetzer protoboards. I may take one and do this and the Nouspikel USB, both of them, on it, for the peb box. 1 Quote Link to comment Share on other sites More sharing options...
+FarmerPotato Posted February 14, 2021 Share Posted February 14, 2021 On 2/11/2021 at 4:05 PM, Madhatter1 said: There is no PCB and I don't intend to make one. I built this using wire wrap for myself. I never know when I will make a change. If someone wants a PCB, They can use KICAD to make one. I wished I would have used Eagle, Because Eagle is now part of Fusion 360. In which case I could have milled a PCB on my CNC. This ATMEGA162 emulates the disk controller and interfaces to the TI DSR rom. Nice! I use wire wrap too So this acts like a drive attached to the TI controller? Or do you mean it has its own DSR ROM replaces the need for a controller? 1 Quote Link to comment Share on other sites More sharing options...
Madhatter1 Posted February 14, 2021 Author Share Posted February 14, 2021 15 hours ago, FarmerPotato said: Nice! I use wire wrap too So this acts like a drive attached to the TI controller? Or do you mean it has its own DSR ROM replaces the need for a controller? It uses the TI DSR rom. I wanted it that way so it would be total compatible. 1 Quote Link to comment Share on other sites More sharing options...
Madhatter1 Posted February 15, 2021 Author Share Posted February 15, 2021 8 hours ago, Madhatter1 said: I miss read your question. It is complete, you do not need a TI disk controller. 2 Quote Link to comment Share on other sites More sharing options...
+arcadeshopper Posted March 4, 2021 Share Posted March 4, 2021 I'm going to try and build a PCB for this that will plug in to the sidecar memory card/TIPI 44 pin stack Greg 3 Quote Link to comment Share on other sites More sharing options...
jrhodes Posted March 4, 2021 Share Posted March 4, 2021 (edited) 2 hours ago, arcadeshopper said: I'm going to try and build a PCB for this that will plug in to the sidecar memory card/TIPI 44 pin stack Greg Awesome. Love my tipi, but this thing is going to be interesting to mess with. Already got a nonopeb on my spare ti, but i may just replace it with one of these if it lives up to expectations. Edited March 4, 2021 by jrhodes 2 Quote Link to comment Share on other sites More sharing options...
+Vorticon Posted March 5, 2021 Share Posted March 5, 2021 Does it require an external power supply or is it powered directly by the TI? Quote Link to comment Share on other sites More sharing options...
Madhatter1 Posted March 8, 2021 Author Share Posted March 8, 2021 I powered it from the TI bus 1 Quote Link to comment Share on other sites More sharing options...
Madhatter1 Posted March 8, 2021 Author Share Posted March 8, 2021 I'll correct the D6 & D7 mistake and flag the unused inputs, Thank you. I built this using wire wrap and never intended to make a PCB. It is working. I have been using it for a couple years. You can find a SD module on ebay for a couple dollars. It will take care of the 3v logic to 5v TTL. BOM is what you see n the schematic. I did make change from ATmega8515 to ATmega162. The 162 has more ram allowing me to read a full 512 byte sector from SD card. With ATmega8515 I original was only using 256 bytes of sector and would have to double the disk image file. That allows me to directly copy and modify disk image on PC. 7 Quote Link to comment Share on other sites More sharing options...
Madhatter1 Posted March 9, 2021 Author Share Posted March 9, 2021 I have cleaned up the ERC errors and uploaded new schematic 4 Quote Link to comment Share on other sites More sharing options...
Madhatter1 Posted March 9, 2021 Author Share Posted March 9, 2021 I just realized there are no decoupling capacitors in the schematic. Since I added them in as was wiring the power bus. You could just solder them directly across the power pins of the ICs Or If someone wants to add them to schematic before making a PCB. 2 Quote Link to comment Share on other sites More sharing options...
Shift838 Posted April 20, 2021 Share Posted April 20, 2021 (edited) On 3/8/2021 at 11:35 PM, Madhatter1 said: I just realized there are no decoupling capacitors in the schematic. Since I added them in as was wiring the power bus. You could just solder them directly across the power pins of the ICs Or If someone wants to add them to schematic before making a PCB. A few questions. Looks like the 2N3904 has the same symbol but has the pin #'s in different locations. Locations do not look mirrored, so I'm wondering why and if we follow the schematic symbol for the wiring or the actual parts pin #'s on the schematic See attached pic. I believe the one on the right is correct as it has the standard layout, but the other 2N3904 the pin #'s do not match the standard layout. Edited April 21, 2021 by Shift838 1 Quote Link to comment Share on other sites More sharing options...
atrax27407 Posted April 20, 2021 Share Posted April 20, 2021 The TI Disk Controller DSR is burned into two (2) TMS2532s. Quote Link to comment Share on other sites More sharing options...
Shift838 Posted April 20, 2021 Share Posted April 20, 2021 (edited) 15 minutes ago, atrax27407 said: The TI Disk Controller DSR is burned into two (2) TMS2532s. yes on the original TIFDC it does. It looks like @Madhatter1used a 2764 to be able to fit both 2532 code into one 2764. Edited April 20, 2021 by Shift838 1 Quote Link to comment Share on other sites More sharing options...
Madhatter1 Posted April 22, 2021 Author Share Posted April 22, 2021 The one on the right is correct EBC. I'll correct the schematic. Quote Link to comment Share on other sites More sharing options...
oddemann Posted April 22, 2021 Share Posted April 22, 2021 New to all this "make it yourself!" I have no clue how to open up the PCB file. The tools for Windows, I kinda get, but I need to make a PCB and then put all the parts on. But... what software should I use to open up all of this? So I have time to understand all the stuff, but I need to start with the PCB and order that with the parts. And then I can tackle the stuff to make an image and all that. Quote Link to comment Share on other sites More sharing options...
Shift838 Posted April 22, 2021 Share Posted April 22, 2021 9 hours ago, oddemann said: New to all this "make it yourself!" I have no clue how to open up the PCB file. The tools for Windows, I kinda get, but I need to make a PCB and then put all the parts on. But... what software should I use to open up all of this? So I have time to understand all the stuff, but I need to start with the PCB and order that with the parts. And then I can tackle the stuff to make an image and all that. I have used a few different PCB design software packages. Eagle and Kicad are both good options. I lean myself more to Eagle as it is now integrated with Fusion 360. Quote Link to comment Share on other sites More sharing options...
oddemann Posted April 22, 2021 Share Posted April 22, 2021 3 hours ago, Shift838 said: I have used a few different PCB design software packages. Eagle and Kicad are both good options. I lean myself more to Eagle as it is now integrated with Fusion 360. EAGLE is now only available with a Fusion 360 subscription. - To bad! But thx for the tips! Quote Link to comment Share on other sites More sharing options...
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