Jump to content


New Members
  • Content Count

  • Joined

  • Last visited

Community Reputation

36 Excellent

About Madhatter1

  • Rank
    Combat Commando

Recent Profile Visitors

375 profile views
  1. The one on the right is correct EBC. I'll correct the schematic.
  2. 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.
  3. I have cleaned up the ERC errors and uploaded new schematic
  4. 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.
  5. I powered it from the TI bus
  6. I miss read your question. It is complete, you do not need a TI disk controller.
  7. 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.
  8. 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
  • Create New...