wanted: Apple II plus Language Card or RAMCARD schematic

[lites]

Hello. I'll plan to make 16KB ram card board by using programmable
logic devices, but I need the schematic of the CARD.

The ram card is consist of 16Kbit DRAMs and some logic gate ICs.

Could anyone give the schematic of the card or describe the diagram?
Please, help me.

[Henry]

By 16k RAM card do you mean the II Language card?

May I ask what kind on PLD's you plan on using?


Henry S. Courbis
www.GSE-Reactive.com

Post by lites
Hello. I'll plan to make 16KB ram card board by using programmable
logic devices, but I need the schematic of the CARD.
The ram card is consist of 16Kbit DRAMs and some logic gate ICs.
Could anyone give the schematic of the card or describe the diagram?
Please, help me.

[David Wilson]

Post by lites
Hello. I'll plan to make 16KB ram card board by using programmable
logic devices, but I need the schematic of the CARD.
The ram card is consist of 16Kbit DRAMs and some logic gate ICs.
Could anyone give the schematic of the card or describe the diagram?
Please, help me.

The schematic can be found on page 5-27 of "Understanding the Apple II"
by Jim Sather (ISBN 0-912985-01-1) - if you cannot source this I should
be able to scan it or take a picture of it. It is a bit difficult to
describe (and not directly usable unless you intend to use 4116 RAM
chips). It would be much simpler to use a 62256 static RAM chip and a
PLD - you avoid the need for the cable to the motherboard RAM array.

[mspangler]

Post by David Wilson
The schematic can be found on page 5-27 of "Understanding the Apple II"
by Jim Sather (ISBN 0-912985-01-1) - if you cannot source this I should
be able to scan it or take a picture of it. It is a bit difficult to
describe (and not directly usable unless you intend to use 4116 RAM
chips). It would be much simpler to use a 62256 static RAM chip and a
PLD - you avoid the need for the cable to the motherboard RAM array.

Applied Engineering sold a SRAM based language card. That schematic
would be useful. For that matter, a new source of IO32 cards (a pair of
6821 PIAs and a Rom that I assume had some routines that ran off of
ampersand routines) would be great too.

Mike S

[Michael J. Mahon]

Post by mspangler

Post by David Wilson
The schematic can be found on page 5-27 of "Understanding the Apple II"
by Jim Sather (ISBN 0-912985-01-1) - if you cannot source this I should
be able to scan it or take a picture of it. It is a bit difficult to
describe (and not directly usable unless you intend to use 4116 RAM
chips). It would be much simpler to use a 62256 static RAM chip and a
PLD - you avoid the need for the cable to the motherboard RAM array.

Applied Engineering sold a SRAM based language card. That schematic
would be useful. For that matter, a new source of IO32 cards (a pair of
6821 PIAs and a Rom that I assume had some routines that ran off of
ampersand routines) would be great too.

A Mockingboard is a 32-bit parallel I/O card.

There are two 6522's each of which provides two 8-bit bidirectional
ports. Of course, for each 6522 one of the ports (and a couple bits
of the other) is hooked up to an '8910.

But each '8910 has an 8-bit port, too--accessible indirectly through
the 6522! (It's not as clever as the 6522 ports, but it's there--
and almost never used.)

Any card with a 6522 on it begs to be used as a timer, shifter,
parallel port, interrupt source, etc. I find the 6522 much more
interesting than the '8910 it drives. ;-)

-michael

Music synthesis for 8-bit Apple II's!
Home page: http://members.aol.com/MJMahon/

"The wastebasket is our most important design
tool--and it is seriously underused."

[lites]

Excuse me for deleting my first post. BTW, I get it a moment ago.
(^_^).

I will probably use spartan or cyclone fpga. Actually, I'll integrate
II+ mainboard too.

Planning stage yet.

If I succeed, I'll post it here too. Thank you for fast responses.

[PZ]

You can scrap all of the DRAM refresh logic just by using SRAMS.
32kx8's are cheaper than dirt these days. 4 of 'em and you have a 128k
machine.

- Paul

[h***@freenet.de]

I can mail you an unofficial schematic of the Apple Language Card.
Someone retraced it so there may be some errors included.

Is you email-address valid?

bye
Marcus

[lites]

Marcus, my email address is valid.
I got MS ramcard, but it will be welcome if you send the file to my
e-mail address.
Thank you for kindness.
Regards.

[Mark McDougall]

Post by lites
I will probably use spartan or cyclone fpga. Actually, I'll integrate
II+ mainboard too.

Woah! That's way overkill! An FPGA probably has enough internal RAM to
emulate the language card!!!

Regards,

[Alex Freed]

Post by Mark McDougall
Woah! That's way overkill! An FPGA probably has enough internal RAM to
emulate the language card!!!

Yes, along with 6502 and just about everything else. See my

http://www.mirrow.com/FPGApple


As for the language card, here is the Verilog logic that is know to work:


module ramcard(mclk28,reset_in,strobe,addr,ram_addr, we,
card_ram_we,card_ram_rd, bank1);
input mclk28;
input reset_in, strobe;
input [15:0] addr;
output [15:0] ram_addr;
input we;
output card_ram_we;
output card_ram_rd;
output bank1;

reg bank1, read_en, write_en, pre_wr_en;
wire Dxxx;

always @(posedge mclk28) begin
if(reset_in) begin
bank1 <= 0;
read_en <= 0;
write_en <= 1;
pre_wr_en <= 0;
end else begin
if((addr[15:4] == 'hC08) & strobe) begin
bank1 <= addr[3];
pre_wr_en <= addr[0] & ~we;
write_en <= addr[0] & pre_wr_en & ~we;
read_en <= ~(addr[0] ^ addr[1]);
end
end
end

assign Dxxx = (addr[15:12] == 4'b1101);
assign ram_addr = {addr[15:13], addr[12] & ~(bank1 & Dxxx) , addr[11:0]};
assign card_ram_we = write_en;
assign card_ram_rd = read_en;

endmodule

[Mark McDougall]

Post by Alex Freed
Yes, along with 6502 and just about everything else. See my
http://www.mirrow.com/FPGApple

... or mine... ;)

<http://members.iinet.net.au/~msmcdoug/pace/Nanoboard/nanoboard.html>