Jump to content

ctirad

Members
  • Content Count

    307
  • Joined

  • Last visited

Community Reputation

147 Excellent

About ctirad

  • Rank
    Moonsweeper
  • Birthday 10/22/1976

Profile Information

  • Gender
    Male
  • Location
    Prague, CZ/EU

Recent Profile Visitors

13,196 profile views
  1. Just for the record. More than a year ago I started a similar project base on the FPGA. It outputs directly HDMI and VGA 576p signal (exactly doubled PAL timing, thus no tearing). I have no time to work on it, because I'm totally overhelmed by my day work projects, so I'd like to release it as opensource. But I need to coopoerate with someone that would help me to setup all the things like GIT for that. Any volunteers? Current status is: Standard modes: done hires modes: done GTIA modes: done (with a small bug) PMGS: broken and unfinished pallete: done (borrowed from altirra for now) GTIA logic: NO (has to be paired with a real GTIA fro now) Hardware design: NO (currently developed on the Scarab Spartan6+, but the final design targetted to the Spartan3) The project is acutally more a proof of concept than a real product. It is written in VHDL (Xilinx ISE project) and it a mashup of various pieces of the code from a various opensource products, examples, etc. Thenically it uses the FPGA only without any additional chips except 5V level shifters. The HDMI/DVI is trasmitted directly from the FPGA, same for VGA (+ resistor RGB DAC) and only the internal FPGA RAM is used for the buffers.
  2. It makes not much sense, because my Covox implementatin is neither a simple resistor network nor 4x 8bit dac with parallel input. It uses the CPLD chip for latching of the 4 sample registers, unsigned->signed conversion, digital mixing to 2x9bit stream that is padded to 24bit stream and then streamed over I2S BUS to the true DAC chip with built-in headphone amplifier (Wolfson). The standalone implementation would save only the SRAM chip, that makes barely 1/5th of the component price.
  3. Just a basic 576kB or 320KB with remapped base RAM (useful mainly for 16kB 600XL machines). Due to fact, the PBI port lacks /HALT signal needed for separate CPU/ANTIC makes, there was no reason to bother with a true 130XE and COMPY modes.
  4. The RAM 576XL is finished, but unfortunately I have no time to start a mass production
  5. Just a quick info. The project is currently in hibernation. Actually, it is not a problem for me to sit and route the PCB in a couple of hours and send it to the manufacturer. The problem is the price. The PCB has to be quite big, say 2 or 3 time bigger than RAM320XE PCB. It will not be cheap. If goldplated, the price will be even higher. Also there has to be either an enclosure or at least some clever made legs to make it firmly tied with the atari. So I'm asking, what price would be acceptable for you?
  6. Hi there. I have still ~20 units left. To place an order, plese see the first post in this thread for details and then write me a PM with the desired configuration.
  7. PM sent. 576kB is actually a plenty of RAM. With my current knowledge I belive the solderless 1088kB is possible, although very tricky. However, I'm not going to produce such a card in the near future if ever.
  8. I have single unit left somewhere but it does need to be fixed first.
  9. Manual is included here: RAM320XE_english_unfinished_v3.pdf
  10. 1) No problem with RAM 320XE/576 production. I have a plenty of cards ready to send. 2) I have some general stability problems with the prototype of 576XL. I had no time so far to debug it precisely with an oscilloscope and a logic analyser.
  11. It is not just out of the tune, it is totally disharmonic cacophony most of the time. I just heard the original sid/mod version and it sounds perfectly correct.
  12. Pros: The RAM320XE/576 has more compatible 576kB mode (real RAMBO) , true 130XE and 320XE modes with separate CPU/ANTIC banking and option to completely disable and remap internal 64kB RAM to the external RAM. Optional Covox audio nice LEDs that indicates when ROM and BASIC are mapped Cons: No 1MB (altough I'm able to design an external 1MB version, I don't think it is useful) No Flash for ROM/CART images - hmmm, it would be actually pretty nice to have Qmeg ROM without need to open a machine. Maybe later. No RTC
  13. Please see the very first post in this thread.
×
×
  • Create New...