[HN Gopher] Recreating the Canon Cat document interface
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Recreating the Canon Cat document interface
Author : tonyg
Score : 77 points
Date : 2025-10-15 14:42 UTC (8 hours ago)
(HTM) web link (lab.alexanderobenauer.com)
(TXT) w3m dump (lab.alexanderobenauer.com)
| drivers99 wrote:
| > The hard part is that the Canon Cat had bespoke hardware with
| dedicated keys for its actions
|
| I actually designed a PCB / custom keyboard (well, it's just a
| copy of the Canon Cat layout) with the Leap, Use Front, etc keys
| (using an ARM dev board called Black Pill, which is probably
| overkill, to scan the rows/columns for key up/down events) for
| this reason. Right now I have it sending key codes over a serial
| connection to another microcontroller with a display module so
| you can now type on it, but I really need to get started on the
| actual Canon Cat style software. I'm not really planning to make
| it USB compatible or use any existing OS though.
|
| > Maybe predictably, early on I found myself wanting more than
| one text stream. I fought that inclination to discover what's in
| store down the pure Canon Cat path.
|
| I think the Cat would let you do that if you used multiple disks?
| I haven't used a Canon Cat, but only read the documentation. It
| used a single DISK button for loading and saving, based on
| context. The following quote is copied from the manual for
| reference. I think the "beep" option is for if you've made an
| edit in memory but don't have the correct disk in for saving that
| same text stream.
|
| [quote]
|
| The Cat has two storage places for your text: memory and disk.
| Memory is the area inside the Cat where the text is stored while
| you are working on it. The on-screen text is a portion of the
| text stored in memory. The memory is kept alive by the electric
| current coming from the wall. If the power were cut, the text in
| the memory would be lost, so you need to record the text more or
| less permanently on a disk with the help of the disk drive.
|
| One command, [DISK], handles all operations involving disk and
| memory. When you use [DISK], the Cat does one of three things:
|
| - _Plays back_ the disk in the drive. This means copying the
| information from the disk into the memory, and putting a portion
| of it up on the screen where you can see it and work on it.
|
| - _Records_ the text in memory. This means transferring the
| information in memory to the disk for safe storage.
|
| - _Beeps_. This means the Cat makes a warning sound and does
| nothing, because recording or playing back might lose
| information.
|
| A DISK sign appears on the ruler while the Cat is recording or
| playing back.
|
| [unquote]
| kragen wrote:
| This does mention Archy, but not in any depth. It doesn't mention
| _The Humane Interface_
| (https://en.wikipedia.org/wiki/The_Humane_Interface), THE, or
| RCHI. I wonder what the reason is for these omissions? You'd
| think they'd be central to any discussion of recreating the Canon
| Cat document interface!
|
| _Bootstrapping Computing_ looks interesting.
| drivers99 wrote:
| I wasn't familiar with (or had forgotten) those acronyms nor
| Archy. Looks like RCHI stands for Raskin Center for Humane
| Interfaces. THE stands for The Humane Environment which is what
| Archy used to be called.
| https://en.wikipedia.org/wiki/Archy_(software)
|
| Sounds like it had the problem of not using a custom keyboard.
| kragen wrote:
| Yup.
| anthk wrote:
| >keys
|
| Under Emacs or X11 you can nearly map every key/keybinding to
| anything.
|
| Also, on The Humane Interface, and the "Undo for everything"...
| Emacs has desktop-mode and for sure it could be set to
| save/restore nearly everything.
| https://en.wikipedia.org/wiki/The_Humane_Interface
| GavinAnderegg wrote:
| I just learned about the Canon Cat a couple of days ago! I wrote
| up a blog post with some resources and tidbits:
| https://anderegg.ca/2025/10/13/the-canon-cat
|
| I had a lot of fun with this emulator on Archive.org, and
| included some quick notes about using it with macOS:
| https://archive.org/details/canoncat
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