Now I make PCB design (4 layers). Some years ago I work on ZX ula clone, SAM COUPE asic is not so harder. ASIC replacement is impossible make in one CPLD chip, then I have one XC95288XL + second CPLD. Your EPM7128SLC84 is usable only as ZX ula replacement, very small. I have all components, don't need next. I use two SRAM chips 512kB x 16bit (=1MB in one chip) with 10ns speed. Final CPB will very small and can be used in real sam coupe case as replacement of original SAM's board (need connect next PCB with connectors for back panel). Flash eeprom is type 29F040 = 512kB. EEPROM chip will work only after power-on, later will copy sam rom image from eeprom chip to extended fast ram memory and here will work instead sam rom (rom emulation in ram - this enable load/rewrite sam rom).
VELESOFT ----- Original Message ----- From: Leslie Anderson To: [email protected] Sent: Sunday, March 24, 2013 6:17 PM Subject: Re: Sam Coupe project..making a real SAM in hardware ?? It sounds like a great project. How far are you on with your design ?? Are you putting it onto a PCB or something else ? I have quite a few components laid around if you want any ... CPLD EPM7128SLC84s, Z84C0020PECs, W27C512s.. I've only got SRAMs 128k x8bit or 512K x 8 bit 55ns or 70ns. On 24 March 2013 16:50, VELESOFT <[email protected]> wrote: I now work on my project SAM COUPE clone :-D Z80CPU 20MHz 2MB RAM (16bit fast data bus) 512kB FLASH EPROM CPLD chips as ASIC replacement and next features... SAA1099 soundchip System bus compatible with sam coupe ZX mode compatible with ZX128 VELESOFT ----- Original Message ----- From: Leslie Anderson To: [email protected] Sent: Sunday, March 24, 2013 3:28 PM Subject: Sam Coupe project..making a real SAM in hardware ?? Hi. I'm new to the SAM COUPE group and wondered would anyone be interested in making a homebrew SAM-COUPE ?? It would have an improved spec. on the original: Z84C0020 20MHz Z80 512K SRAM ( KM68400,K6T4008 etc) 64K or so EEPROM W27C512 CPLDs as glue logic for video, memory and I/O decoding, serial and parallel input,output RS232, LPT1 etc SAA1099 sound chip V9958 +128K RAM as second VDP for sprites etc possible using a micro-controller for PS/2 mouse / keyboard and joystick input. Should cost about £30 for ICs and stuff plus another £50 for a one-of prototype PCB. Anyone interested ?? Best Regards
