Post by oompa loompa on Nov 17, 2005 17:31:00 GMT -5
howdy ho
just last week, i started building another z80 system from scratch. i designed the system a couple weeks ago, the design took a while to turn into reality due to the constraints on what parts i'd like to use.blah, blah, blah, anyways, here's the system specs:
- Z80 microprocessing power !!! running at 24 mhz (the cpu actually runs at 16 mhz overall when displaying the screen) power !!!
- 32k ram for programs+work memory+video memory power !!!
- 30k flash memory for os+toolbox power !!!
- 288x208 black and white composite video output power !!!
- IDE bus connector to interface a hard drive, or cd rom.... power !!!
- ps/2 keyboard interface power !!!
- sega/atari joystick interface power !!!
- runs on a 9v battery power, only sinking 100mA power !!!
- up to 4 video modes: 1) display segmented into 36x26 using 8x8 tiles with two scrollable planes, 2) display segmented into 48x26 using 6x8 tiles with only one scrollable plane, 3) dual frame buffer mode, 4) one plane segmentation of 18x13 using 16x16 tiles with another plane (window) using 6x8 tiles
- no way to expand the system power !!!
- 1 bit audio beeping and booping power !!!
- an 8 bit parallel port with 4 bits of hardware handshaking power !!!
here's some pics of this MONSTER computer:
the pcb occupied with the integreated circuits. up on the left top is the toshiba z80 cpu, to the right is the sync controller for the video (also serving as the oscillator circuit) with the 24 mhz crystal on its right. on the middle row, starting from the left you'll see the 32k ram busted off a 486, the programmable logic chip, and the video shift register. on the bottem row, there's the 32k of flash memory, and then the 8255 programmable i/o controller
the pcb without any parts. all wires are really short because i routed them under the sockets ;D!
the back side of the pcb, all points and wires were soldered on by hand
i finished the entire fabrication of the pcb somewhere around last friday, right at the end of exams =P. basically, the main function of this design with so little parts with video outputting power is to make the cpu do the drawing for you without the use of a dedicated crt controller. it is much cooler because then i get to use the z80 to organize the tiles and such (like the genesis, or gameboy 0o0o0), and not have to go with just using a frame buffer. the only problem is that the cpu is only meant to run at 8 mhz, but i've overclocked the sucker to 24mhz =P. the cpu runs very stable though, and i've tested the computer, making it run for an entire day, while running an led blinking code (in addition to the video generating code), without having it lock up. haven't had time to start making a descent OS yet (was planning on porting CP/M 2.2, but dunno where to start =P).
o wait ! i also haven't put the ide connector, or i/o connector on the pcb yet (which will occupy the empty pcb space below the board)
so, there's your eye candy for today =D
just last week, i started building another z80 system from scratch. i designed the system a couple weeks ago, the design took a while to turn into reality due to the constraints on what parts i'd like to use.blah, blah, blah, anyways, here's the system specs:
- Z80 microprocessing power !!! running at 24 mhz (the cpu actually runs at 16 mhz overall when displaying the screen) power !!!
- 32k ram for programs+work memory+video memory power !!!
- 30k flash memory for os+toolbox power !!!
- 288x208 black and white composite video output power !!!
- IDE bus connector to interface a hard drive, or cd rom.... power !!!
- ps/2 keyboard interface power !!!
- sega/atari joystick interface power !!!
- runs on a 9v battery power, only sinking 100mA power !!!
- up to 4 video modes: 1) display segmented into 36x26 using 8x8 tiles with two scrollable planes, 2) display segmented into 48x26 using 6x8 tiles with only one scrollable plane, 3) dual frame buffer mode, 4) one plane segmentation of 18x13 using 16x16 tiles with another plane (window) using 6x8 tiles
- no way to expand the system power !!!
- 1 bit audio beeping and booping power !!!
- an 8 bit parallel port with 4 bits of hardware handshaking power !!!
here's some pics of this MONSTER computer:
the pcb occupied with the integreated circuits. up on the left top is the toshiba z80 cpu, to the right is the sync controller for the video (also serving as the oscillator circuit) with the 24 mhz crystal on its right. on the middle row, starting from the left you'll see the 32k ram busted off a 486, the programmable logic chip, and the video shift register. on the bottem row, there's the 32k of flash memory, and then the 8255 programmable i/o controller
the pcb without any parts. all wires are really short because i routed them under the sockets ;D!
the back side of the pcb, all points and wires were soldered on by hand
i finished the entire fabrication of the pcb somewhere around last friday, right at the end of exams =P. basically, the main function of this design with so little parts with video outputting power is to make the cpu do the drawing for you without the use of a dedicated crt controller. it is much cooler because then i get to use the z80 to organize the tiles and such (like the genesis, or gameboy 0o0o0), and not have to go with just using a frame buffer. the only problem is that the cpu is only meant to run at 8 mhz, but i've overclocked the sucker to 24mhz =P. the cpu runs very stable though, and i've tested the computer, making it run for an entire day, while running an led blinking code (in addition to the video generating code), without having it lock up. haven't had time to start making a descent OS yet (was planning on porting CP/M 2.2, but dunno where to start =P).
o wait ! i also haven't put the ide connector, or i/o connector on the pcb yet (which will occupy the empty pcb space below the board)
so, there's your eye candy for today =D