Hi.
I didn't realise github can host pages - interesting... always learning something new. I'll do some investigating.
The x10hosting site where I now hold my files offers unlimited traffic and seem to be a decent speed and gives an easy ftp upload so I can throw files up there easily, but anything ...

Hi.
[Already posted this message elsewhere, but including it here in case you didn't know]

I have given up with the existing web hosting - they banned me because they said I was getting too many hits and instead of throttling as they used to, they now just say I violated their T&Cs and take me down ...

Hi.
I have given up with the previous web hosting - they banned me because they said I was getting too many hits and instead of throttling as they used to, they now just say I violated their T&Cs and take me down !!
So, I have now purchased my own domain (searle.wales) and put my files on a ...

Hi.
Sorry that my pages were down. Glad you found them on archive.org. There was an issue on the web hoster side that wrongly flagged an issue with my site. All back up and running now :)

http://searle.hostei.com/grant/6502/Simple6502.html
http://searle.hostei.com/grant/z80/SimpleZ80.html

etc ...

Hi Alarmorobotics.
Yes, the projects are suitable for beginners - it is intended to give a complete walkthrough or what is needed and an introduction to FPGAs and the VHDL that is used. Everything you need to type in is included on the page, and once you become familiar with what is going on then ...

Hi Bill.
No changes apart from the pins would be necessary assuming you have the same clock speed.

If you have a different clock then either change the relevant timing values (a bit tedious) or introduce a PLL into the design.

ie. in_clk ------> PLL logic ------> 50MHz clk

Regards.

Grant

Hi.
Been a while since I checked the calculations, but the ram on the page is fine. I'd need to dig out the timings but from what I recall there was sufficient time between the selection and the read / write due th the Z80 requiring multiple clocks for each operation.
The wires I used are about 4 ...

If it's not for CP/M then the 64kbit (8Kbyte) chip is fine.
Connect all of the address lines that are available on the chip - don't worry about the top addresses (a15, a14 and a13) mentioned on the board pinout - leave them disconnected.

Then, follow the instructions on my page for using the 8K RAM ...

No, to use JTAG plug the blaster into the relevant port, then swap the connector to the AS port if you want to use active serial. The USB Blaster is used for both.

Yes, the download screen is what is needed, but you can un-tick the modelsim if you won't be using it (not needed for development ...

Hi Mike.
All you need are the core download ("Quartus II Web Edition (Free)") and the cyclone devices ("Cyclone II, Cyclone III, Cyclone IV device support (includes all variations)").
You can "un-tick" the other devices unless you want them.

Very big download, unfortunately. Thankfully I am on a ...

Brill.
Glad it's working for you

All the best.

Grant

Hi YT2095.
I have eMailed you the complete set of files (as uploaded), updated with the changes to use external RAM and also 80 columns.

Please let me know how you get on - definitely works for me (and others).

Regards.

Grant

Hi.
I'll see if I can eMail you later a zip of the complete project that is working on mine (80 column, extended RAM) so that you can double-check if there is a VHDL issue somewhere. I'll use the published code and changes on my page.

Very odd because it is OK for myself and others.

Anyway, try ...

Hi YT2095.

I have replied to your issue via eMail. There was an error in your top level VHDL (and need to check the display VHDL changes as it shouldn't have compiled OK). With the fix it all works fine for me.

Regards.

Grant

Hi.
Please can you eMail me your VHDL (eMail address can be found on the link at the bottom of the web page) and I'll check it on mine and get back to you.

Several others have built it so the wiring on the page should be fine.

Regards.

Grant.