Paul Gardner-Stephen
c65gs.blogspot.com · Personal blog · on HN since 2015
Paul Gardner-Stephen develops the MEGA65, an FPGA-based recreation of the Commodore 65, and writes about its hardware, ROMs, and software.
What HN saysCommenters call it a blog with great development content and point to it as the work of someone recreating the Commodore 65 that never shipped.
18HN people shared it
10linked it in comments
28stories submitted
463story points
12 months agolast shared
2015people per year2026
Most-shared posts
- 1HD floppies, RLL encoding, disk density auto-detection and other fun2 people · 33 points · first shared 2021 · 8 comments on HN
- 2Mega65 Keyboard prototypes have been manufactured1 people · 90 points · first shared 2018 · 26 comments on HN
- 3Making a C64/C65 compatible computer in an FPGA1 people · 76 points · first shared 2017 · 17 comments on HN
- 4Fixing the Oldest and Nastiest Bug in Commodore Basic1 people · 64 points · first shared 2021 · 6 comments on HN
- 5Improving the C65 ROMs1 people · 53 points · first shared 2021 · discussion on HN
- 6Porting a Wolfenstein-type engine to the MEGA651 people · 47 points · first shared 2020 · 5 comments on HN
- 7Working on the “Web” Browser for the MEGA651 people · 42 points · first shared 2022 · 4 comments on HN
- 8Making a C64/C65 compatible computer: MEGAphone contact list and Dialer1 people · 19 points · first shared 2025 · discussion on HN
- 9Switching from CC65 to LLVM-MOS for the MEGA65 Browser1 people · 7 points · first shared 2024 · discussion on HN
- 10Starting Work on a Libc for the MEGA651 people · 4 points · first shared 2020 · discussion on HN
- 11DIY USB JTAG and UART Connection for the MEGA651 people · 2 points · first shared 2022 · discussion on HN
- 12Working on Composite Video Output for the MEGA65 Expansion Board1 people · 2 points · first shared 2023 · discussion on HN
- 13Working on Floppy Writing1 people · 2 points · first shared 2021 · discussion on HN
- 14Work on floppy formatting, CRC calculation and sector writing1 people · 2 points · first shared 2021 · discussion on HN
- 15MEGA65: Pulling out the big guns for improving compatibility with HDMI monitors1 people · 2 points · first shared 2020 · discussion on HN
What HN people wrote when they linked it
SwellJoe · 2015-04-23
The author's blog has some great stuff about development: http://c65gs.blogspot.de/
rasz · 2024-04-09
This will just make gaps between sectors bigger, lowering capacity given standard bitrate and rotation speed.
The point of zone bit recording (ZBR) / zoned constant linear velocity (ZCLV) is to pack mode data on the outside (longer) cylinders. Doing some back of napkin calculations the most Outer track has circumference of ~27 cm while inner is ~18cm long. Outer track should be able to fit 1.5 x magnetic flips while staying in spec.
If you want even more data you go GCR all the way to RLL encoding. Fantastic dev blog documenting implementation of 3.5 Inch HD (2.7)RLL Floppy Controller for use in MEGA65 project: https://c65gs.blogspot.com/2022/01/more-work-on-hd-floppies-rll-encodi… Over 3MB out of standard 1.44MB drive/floppy by combining both zone recording and RLL.
basementcat · 2023-12-19
Mac drives had finer control over the motor RPM. Amiga drives read/wrote a track at a time and had no sector gaps.
https://porterolsen.wordpress.com/2016/06/15/accessing-mac-formatted-f…
https://c65gs.blogspot.com/2023/10/reading-amiga-disks-in-mega65.html?…
blue1 · 2015-08-26
I believe this guy http://c65gs.blogspot.it/ is doing something like that, recreating the Commodore 65 that never was.
bwldrbst · 2015-02-17
Here's the blog of a guy who's building a machine based on it: http://c65gs.blogspot.com.au/
dfxm12 · 2022-06-03
So I'd be really curious to know how they managed that part of the whole thing.
Searching the linked development blog yields this: https://c65gs.blogspot.com/2019/03/floppys-floppys-everywhere.html
After some searching, we found what we were after: A local supplier here in Germany who has some quantity of different models, including a large number of ALPS 3.5" 1.44MB drives.
cable2600 · 2021-05-22
It is still in beta test and they have a free emulator and the ROM is open source. It is a Commodore 65 clone, which is like a cross between an Amiga and Commodore 64. It has Amiga graphics and sound. It also has a C64 mode.
Only developers can buy a computer and it is expensive, once it hits retail they will make them in mass production to keep costs down.
https://c65gs.blogspot.com/2020/07/mega65-emulator-and-tools-live-iso.…
BallyBrain · 2020-07-01
Extra links for further information:
https://mega65.org/
https://c65gs.blogspot.com/2020/06/ultrasonic-communications-for-mega6…
sgt · 2015-04-23
Also see Paul Gardner-Stephen's blog entry "Introducing the MEGA65 Retro Computer"
http://c65gs.blogspot.de/2015/04/introducing-mega65-retro-computer.htm…
draven · 2015-04-23
This post:
http://c65gs.blogspot.de/2015/04/c65gs-at-revision-2015-and-running-on…
mentions a "c64 mode" on the c65gs (the basis for this machine.)
It would be awesome if that machine gets used at demoparties.