Jump to content


New Members
  • Content Count

  • Joined

  • Last visited

Community Reputation

14 Good

About gianlucarenzi

  • Rank
    Combat Commando
  • Birthday 01/16/1971

Profile Information

  • Gender
  • Location
    Imola (BO) ITALY
  • Interests
    Electronics, Computer Science, Retro Computing, American Football, but first of all MY TWO LITTLE LOVELY DAUGHTERS!
  1. Eccomi qua. Dopo anni di stress dovuti all'acquisto di una nuova casa, della nascita di due meravigliose bambine, della convivenza andata male, sono tornato ad avere un po' il passatempo che avevo prima del 2000: l'utilizzo di Atari 8-bit e dell'Amiga. Adesso ci ho aggiunto anche un MSX2... Il primo amore non si scorda mai... Viva il retrocomputing!!! https://github.com/gianlucarenzi visitate un po' il mio repository... Chissa' se non vi viene in mente qualcosa...
  2. Thanks for any advice you gave me. I appreciate them very much. I was looking at the specifications for MIO, and the layout is driving me crazy: let's do an example. I want to write $de $ad at first two bytes of the Bank no.1, then write $be $ef at the address @$80 of bank no.258, then read @$fe of the 25th bank. I will do: lda #1 << 5 ; bit 5 is ram enable sta $d1e2 lda #0 sta $d1e0 lda #0 sta $d1e2 ...write $de $ad @ $d600 lda #$02 sta $d1e0 lda #$01 sta $d1e2; $0102 = 258 ...write $be $ef @ $d680 lda #$19 sta $d1e0 lda #0 sta $d1e2 ...read @ $d6fe As you can see the ram enable bit will go high the first time, then all subsequent write in this register $d1e2 is low. Is it to stay 1 for every ram access? This thing is going me crazy. Are out there some MIO user?
  3. This expansion will be the first of the series. If someone need more ram I should use the Stm32f42x line just to connect ddr2 chip to it and share memory with 6502. It should not so difficult. For now I will focus on a diy project. Bga are too difficult to solder. Can you point me to the apple ii memory expansions?
  4. It should be possible if: - the uart ports are still available in the very few pins available, - someone gives me the 850 R: specifications (xio ioctl codes for setting the baud rate, rts-cts stuff, etc.,...) just to write the right handler.
  5. Here I am again!! Last week I spent a couple of e-mails with Mathy Van Nisselroy talking about MIO's ICD interface and its RAM up to 1Meg. Yesterday I had a mumble mumble and... voila'! Here is my last project! An expansion board for any Atari XE (Having ECI + CART) which sports a UnoCart and a MIO Expansion memory compatible plus a new registers for adding the 2 or 4 megabytes support. It's called DUO Cart (as opposing UNOCart which in italian UNO means ONE, and DUO means TWO ). Its firmware can do all stuff like UNOCart does, plus a MIO Memory expansion. In attachment there are some information and 3d renderings. As soon as the prototypes are ready I will be glad to share everything with you! I hope MyDOS will include this memory expansion driver as it will be 100% compatible, but need a register more to add the extra 2Meg or 4Meg RAM Chips! Best Regards, Gianluca MIO-Registers-Extended.pdf
  6. But it will be a cartridge based RAM expansion (as the cart slot is used and the ECI bus too...). For the beginning I will plan these options: 1- Using PORTB $D301 as bank selector (6-bits) ) so 64 banks can be used (1024k). The other banks selection can go @ $D305... So anyone can use more than 1024k easily... In this case old software can use 1024k and the new one can go up to 4Meg 2- Using PORTB $D301 for total 8 bit. Results will be unpredictable as no OS nor BASIC... ??? I will check with emulator (atari800) 3- Using $D305 for total 8 bits. In this case the only drawback is what will happen using shadowed registers for PIA access... 4- Using $D530 and $D531. PBI device are not banked over here. They can use the address between MPD MathPack and $D800 or other addresses but NO $D5xx (only RTC-8 I think, but not at $30 and $31...) How the Antonia 4Meg works? It need to be installed inside the motherboard?
  7. Thank you for any of your suggestions: all are ok and you surely know what you are talking about. The biggest issue here, is any user who ALREADY HAD an internal expansion on PORTB address (as myself, I have a 576K 130xe done back in the days) will be forced to loose any hardware expansion and de-solder/disconnect everything from their Atari Motherboard. Writing a PBI device I do not see any advantage at all for a memory banked expansion: the driver need to be written anyway. Different story if the expansion is a some kind of GPIO expander, or some sort of sensors like temp sensor or humidity sensors... Regarding the expansion maybe simulating access at $D304 as BANKCTL and $D305 as BANKSEL can be a better option? I suppose any acces in the shadowing address logic (as PORTA and PORTB uses this address too) is not a very good idea. Anyway the access must be written anyway,because no software is using those registers...Another option is to DO NOT CARE what exists inside the Atari and use the PORTB all 8 bits. I suppose some bus contentions for the same addresses or even worstthe memory window at $4000-$7FFF can have sometime the expansion data, and other times the inside-motherboard-chip ram data...Mmmmhhh... Another solution can be use the D1xx access as the Mapping the Atari says...To me the best viable solution is to move the registers up to $D5FE and $D5FF for bankctl and banksel... What hardware is using those two addesses?Regards,Gianluca
  8. Hello, everybody! After 30+ years I would like to keep my ATARI Systems up and running!! I am an Computer Science and Electronic Engineer specialized in microcontrollers and microprocessors. Last year I discovered all my 8-bit systems was kept in the basement of my parents' house. They seemed to be yellowed, the capacitors seems to be NOT LEAKING (but I will replace them ASAP). So I was thinking about to build a memory expansion. I was wondering if anyone will be interested in a PLUG-AND-PLAY (no soldering, no open cases, no drills, no CPU change or whatever) 512K/1M/2M/4M memory expansion using the cartridge bus and the ECI bus present in the rear case of the 130xe. May be with a 50 pin header + edge connectors it can be easly adapted to use in a 800XL and maybe in a 600XL too, but I need to check out everything. This expansion will be COMPLETELY OPENSOURCE, with schematics, Kicad project, Firmware, part list (mouser and digikey and others). It will be a banking scheme type-of-expansion with the memory window at 0x4000 - 0x7FFF without using the PORTB (0xD301) memory control register. In my plan it uses the address @ 0xD530 for banking control, and @ 0xD531 for enable/disable expansion. Actually I cloned the atari800 github project, added the drivers for my expansion and try some memory access on emulator. It works! Application Programming Interface To enable memory expansion write 1 at bank control register @ D531: in C: unsigned char * bankctl = (unsigned char *) 0xd531; *(bankctl) = 1; in ASM: lda #1 sta $d531 in BASIC: POKE 54577, 1 To disable, simply write 0 at the same register. To select the bank (window will be at 0x4000-0x7fff address) write the correct bank number @ register bank select D530: in C: unsigned char * banksel = (unsigned char *) 0xd530; unsigned char * ramwindow = (unsigned char *) 0x4000; *(bankctl) = 12; /* Write at the window of bank 13 */ memcpy(ramwindow, data1, 0x4000); /* Max size will be 16K!!! */ *(bankctl) = 7; /* Write at the window of bank 8 */ memcpy(ramwindow, data2, 0x4000); /* Max size will be 16K!!! */ ... ... in ASM: ; BANK 13 lda #12 sta $d530 ; Do some stuff at address $4000-$7fff ... ; BANK 8 lda #7 sta $d530 ; Do other stuff ad address $4000-$7fff ... in BASIC: REM BANK #8 POKE 54576, 7 .... REM BANK #13 POKE 54576, 12 Pretty simple... ;-P We can have up to 256 memory banks available, so the register can have a number between 0 (bank #0) up to 255 (bank #256). In this way any other memory expansion can be used. In a plain 130XE computer the total amount of memory will be 4096K + 128K - 16K (for the addresses overlapped at the memory window): 4208k!! Basic/ANTIC/... other stuff can be co-exists in this way. Now, I can need some awesome software (MyDOS, SpartaDOS, demos, etc.,) which this expansion can be used. I need feedback please! Thanks!
  • Create New...