Atari 400 Aftermarket Replacement Keyboard Thread

[Rledo]

Hi all

 

i’m really late to this thread.  mobeets.com is still up, but no reply from them.  Assuming I can still buy from mobeets, what would I need to replace my stock keyboard?  I rent right now and all my tools are in storage so I would be willing to pay for assistance 🙂

 

If this can be done, I would want the low-profile switches

[cornchip]

The Mobeet's keyboard is the best upgrade available with one important exception.....no keys available. I built one and am looking for a good home built way to label my own blank DSA key set.

[+scorpio_ny]

2 hours ago, cornchip said:

The Mobeet's keyboard is the best upgrade available with one important exception.....no keys available. I built one and am looking for a good home built way to label my own blank DSA key set.

Hi @cornchip,

Maybe these would fit the bill?

Atari-Non Transparent Keyboard Stickers

 

[Rledo]

On 7/29/2023 at 6:15 AM, scorpio_ny said:

Hi @cornchip,

Maybe these would fit the bill?

Atari-Non Transparent Keyboard Stickers

 

Hmmmm, seems like much surgery involved for my poor old 400.  Besides the mobeets parts, what all did you folks need to do?  Kailh switches, anything else besides the key labels? And is it irreversible or would I be able to use the original membrane keyboard again?

 

Also, I used mobeets contact form on their website, no response so far.  Anyone know if they are still alive?

 

[Geister]

I have tow 400s with B-Key keyboards.  They were reversible until I misplaced the original keyboards.

[Rledo]

3 hours ago, Geister said:

I have tow 400s with B-Key keyboards.  They were reversible until I misplaced the original keyboards.

thx!

[Rledo]

thanks for the replies, everyone!  Michael from mobeets sent me a message..now to decide..

[Donald Dennis]

I really like my "B" key keyboard. Bought one back in the day for the 400 I had back then, but didn't appreciate its utility until I got one installed on my current 400.

[johannesmutlu]

On 11/3/2013 at 1:48 AM, wood_jl said:

The ultimate Atari 400? Well, that would be 48K, a monitor jack (S-video, etc), and a replacement keyboard! How close to the 800 can we come? Those 3 things!

 

But what about the keyboard? It's never *really* going to equal the 800's great keyboard, but how close can it come? What is (was) the best aftermarket 400 keyboard replacement? They still come up on Ebay from time-to-time. Sometimes it's just the keyboard, and other times it's a 400 with the keyboard installed. However, it seems there were at least 3 aftermarket 400 keyboards on the market, and it would be nice to know what they are.

 

I remember one called the "B-key" (or something like that) but I don't remember which one it was. Please chime in an identify these keyboards!

 

Let's call this keyboard "#1." I sort-of think this was called the "B-key" (brand) keyboard, but I seem to recall it was all brown keys, back when I saw one (25 years ago). I could be wrong. What is the particular brand of this keyboard, #1????

 

 

The local Atari dealer had one of these. He told me what it was called, but I can't remember now. Let's call it #2.

 

 

 

What is this called? Never seen one! Anybody seen one? Let's call it #3.

 

 

If there are any others you know of, please post them here. Also, which is the best, in your opinon?

 

Thanks, and take care.

WoooW this atari 400 looks sooo much better with that keyboard replacement,atari should,ve shame for using such cheap ass keyboard for their atari 400,also they should,ve shame for not making the atari 400 48KB ready without grabbing a solder iron and replacing the main bios chip,

but with such moddifications (including composite video mod) the atari 400 get’s transformed into a atari 800-🤣

[Rledo]

1 hour ago, johannesmutlu said:

WoooW this atari 400 looks sooo much better with that keyboard replacement,atari should,ve shame for using such cheap ass keyboard for their atari 400,also they should,ve shame for not making the atari 400 48KB ready without grabbing a solder iron and replacing the main bios chip,

but with such moddifications (including composite video mod) the atari 400 get’s transformed into a atari 800-🤣

AFAIK, Atari targeted the 400 at younger kids, thus the tougher spill-resistant, etc membrane keyboard; it wasn't a question of cost.   Unusable for real work (or even typing BASIC code back in the day)? Yes yes.  Bad idea in hind-sight?  Yes double-yes.

 

Same for the 48K upgrade, which was a bit of a pain to install.

 

[ClausB]

1 hour ago, johannesmutlu said:

shame for not making the atari 400 48KB ready without grabbing a solder iron and replacing the main bios chip,

What? No ROM replacement required.

[Rledo]

5 minutes ago, ClausB said:

What? No ROM replacement required.

I just dug out my installation instructions for the Atari 48K kit (yes, I still have it).  I don't see a ROM replacement.  Don't remember doing it either.  The only thing I objected to was having to break the spacer in the RFI casing = no going back.  The contents of the box were some pre-cut wires and the expansion board.

 

Edited October 17, 2023 by Rledo

[ClausB]

1 hour ago, johannesmutlu said:

shame for using such cheap ass keyboard for their atari 400

No shame at all. Atari made the best possible membrane keyboard, with raised edges for tactile feel and the speaker click which you can feel and hear for feedback. Yes, not good for touch typists, but good enough for entry level in 1979.

[reifsnyderb]

2 hours ago, johannesmutlu said:

WoooW this atari 400 looks sooo much better with that keyboard replacement,atari should,ve shame for using such cheap ass keyboard for their atari 400,also they should,ve shame for not making the atari 400 48KB ready without grabbing a solder iron and replacing the main bios chip,

but with such moddifications (including composite video mod) the atari 400 get’s transformed into a atari 800-🤣

The 400 was originally to be a game machine but has the power to be an entry level home computer for it's time.  Had Atari added a few more connections to the motherboard, adding more than 32k would have been an easy card swap.  With 4 jumpers and the right card it could have as much as 4MB of RAM.  No OS upgrade was necessary.  Fully upgraded, it could be almost as good as an 800.  There is no shame in that.

[BillC]

On 11/2/2013 at 5:48 PM, wood_jl said:

The ultimate Atari 400? Well, that would be 48K, a monitor jack (S-video, etc), and a replacement keyboard!

I still have a 400 upgraded in early 1983 with a Mosaic 64KB RAM board and Inhome B400 keyboard, later added an external 1200XL keyboard connected via ribbon cable. The only item missing is the monitor jack.

[+slx]

5 hours ago, BillC said:

The only item missing is the monitor jack.

If you’re willing to sacrifice the RF cable a female DIN connector on a cable can be routed through the RF cable hole without changing the case. 
 

Reportedly the 400 was to be a console and only got keys to after Doug Neubauer created Star Raiders (which btw makes me wonder if it predated the VCS keyboard controller).

 

IIRC Caverns of Mars was written on a 400/410 combo. While the keyboard wasn’t a joy to type on it was way better than the ZX-81/Timex 1000 because of the click and key „edges“. 
 

[johannesmutlu]

On 10/18/2023 at 12:28 AM, ClausB said:

No shame at all. Atari made the best possible membrane keyboard, with raised edges for tactile feel and the speaker click which you can feel and hear for feedback. Yes, not good for touch typists, but good enough for entry level in 1979.

Well i wonder if there was/is a keyboard overlay alternative,wich you could just slap on top of the atari 400 keyboard to make it more comfortible to use,would be great,also i wonder if homebrewers did tryed to get around that limited 16KB ram by deviding let’s say a 1 MB or 64KB into sections of 16KB and load in one after the other section once needed trough the use of a bankswitching inside the cartride instead rather then trough hardware,so we don’t need to mod the atari 400 but keep it original as it was originally made,sure atari xe games will still not work on the atari 400 that way,BUT if we could moddify those xe games (wich never came out on the atari 400) and use a in game bankswitching chip to bankswitch sections of 16KB once needed,would be great,for instance how about a moddified version of mario bros by splitting it’s 64KB rom into sections of 16KB and load in those 16KB sections one after the other,and just in case the atari 400 lacks the gtia chip unlike the atari xe,we can remap those 256 colorpallet down to approximated colors of a 128 colorpallet with minimum trade offs,why?? So we will have more games on the atari 400 and since mariobros did not came out on the atari 400,that would be really great to see it happen😁

 

 

[+MrFish]

A useful keyboard key (non-shifted) to keep in mind.

 

Also... using several of these consecutively can be beneficial occasionally.

 

[+slx]

4 hours ago, johannesmutlu said:

also i wonder if homebrewers did tryed to get around that limited 16KB ram by deviding let’s say a 1 MB or 64KB into sections of 16KB and load in one after the other section once needed trough the use of a bankswitching inside the cartride instead rather then trough hardware,

If that’s feasible very much depends on what a program actually uses the extra RAM for. If it’s just code what you describe can be done. The XE carts do use bankswitching already, so those using a certain amount of RAM probably use it as working/screen memory. 
 

You could use the graphics of 65XE Debugger (or trap access to certain blocks of RAM on Altirra) to check how a specific program uses RAM. There‘s a thread on XE cart usage as well. 

[johannesmutlu]

2 hours ago, slx said:

If that’s feasible very much depends on what a program actually uses the extra RAM for. If it’s just code what you describe can be done. The XE carts do use bankswitching already, so those using a certain amount of RAM probably use it as working/screen memory. 
 

You could use the graphics of 65XE Debugger (or trap access to certain blocks of RAM on Altirra) to check how a specific program uses RAM. There‘s a thread on XE cart usage as well. 

Yeah i do know that xe games already uses bankswitching BUT is that bankswitching done trough hardware or via software on the cart???

i ask this because for what i do know xe mariobros for instance is 64K so if that entire game has to be first loaded into the 64KB ram of the atari xe and then bankswitch from there,then it doesn’t need a mapper on the cart,otherwise it doe so,

but what if mario bros bankswitches everything in sections of 8KB or 16KB,then we may could port that game to a costum mapper to do it trough software instead and make it run on a atari 400,

HOWEVER, let’s say a xe game is 1MB and it uses a mapper to bankswitch sections of 64KB to the atari xe,then theres no way to port that game to the atari 400 with a mapper because of the limited 16KB ram of the atari 400,or atleast not without heavily removing stuff from the game to make each section of the game fit into 16KB of ram,but that’s the last thing we would ever do as a homebrewer for porting games to the atari 400.

[+slx]

1 hour ago, johannesmutlu said:

Yeah i do know that xe games already uses bankswitching BUT is that bankswitching done trough hardware or via software on the cart???

i ask this because for what i do know xe mariobros for instance is 64K so if that entire game has to be first loaded into the 64KB ram of the atari xe and then bankswitch from there,then it doesn’t need a mapper on the cart,otherwise it doe so,

but what if mario bros bankswitches everything in sections of 8KB or 16KB,then we may could port that game to a costum mapper to do it trough software instead and make it run on a atari 400,

HOWEVER, let’s say a xe game is 1MB and it uses a mapper to bankswitch sections of 64KB to the atari xe,then theres no way to port that game to the atari 400 with a mapper because of the limited 16KB ram of the atari 400,or atleast not without heavily removing stuff from the game to make each section of the game fit into 16KB of ram,but that’s the last thing we would ever do as a homebrewer for porting games to the atari 400.

Atari Carts need to use bank switching on the cartridge in order to contain more than 16K of ROM which is their address space on the machine. AFAIK that space is always $8000 to $BFFF but there are various schemes bank switching schemes that may use $A000 to $BFFF only and have different bank sizes and switching methods, including some that expose RAM "under" the cart. So you might have 2K, 4K or 8K "windows" and two or more banks that switch in there. According to another thread 64K XE carts are

 

Quote

 

Type 13: XEGS 64 KB cartridge

 

This bank-switched cartridge occupies 16 KB of address space between $8000 and $BFFF. The cartridge memory is divided into 8 banks, 8 KB each. Bank H (the last one) is always mapped to $A000-$BFFF. Three lowest bits of a byte written to $D500-$D5FF select the bank mapped to $8000-$9FFF.

 

 

I'd assume the cart uses different banks for different parts of the game According to this thread it needs 64K of RAM but in order to find out what the it does with that RAM you'll have to use a debugger. The 65XE debugger is nice for such stuff because you can see all of memory graphically and at once but on a very quick attempt I didn't manage to find a suitable cartridge image to load. Altirra should be fine for a detailed exploration but you might need a bit more time to find what you need.

 

Basically a cart could just copy game code into RAM and then use it from there or use the RAM for screen/character memory.  If it's the former you might be able to convert it to run from cartridge only. During my quick check I found it to change RAM in the $6000 area, so probably bad luck.

 

Maybe you'll have to wait for the Incognito light for the 400. In the meanwhile we have to accept that while it's hard to beat the 400's looks' space-age coolness, it has some limitations compared to its bigger and younger siblings.