Build your own ergonomic wireless keyboard!

Lotus 58 - BLE is a fully programmable & customizable wireless split keyboard in the Lotus keyboard family.

Lotus 58 - BLE is the continuation of the classic Lotus 58 - Glow design, but now designed specifically to be wireless using Bluetooth™ BLE and ZMK's excellent firmware, without the compromises of the old design.

Sold as a pair of PCB's, you will need this kit and accessories to make a complete keyboard.

Why a dedicated design?

With a PCB that is designed from the ground up for wireless, the antenna can be placed in a much more optimal position, and power delivery can be optimized for every part. All the while fitting into the outline of the old design without too much compromise, meaning it's mostly compatible with existing cases and plates, depending on your choice in accessories.¹ (Although please avoid metal cases & plates for obvious reasons!)

A low powered display, done the right way. With the low power requirements of the nice!view, it's powered from the nRF52840 chipsets internal regulator with no inefficient regulator/power conversion needed. This means that with the nice!view display on your Lotus 58 - BLE is always powered², and also that it is as efficient as it possibly can be. And since the nice!view is only using power when it's image is actively updated, it has almost no impact on your overall battery consumption.

And if you insist on adding RGB to a wireless keyboard, despite the penalties to battery life, this is now integrated in the most efficent way possible, by powering the RGB directly off of the USB/battery voltage, with no regulator in between. Just like with the nice!nano you can turn off the 'external power' to disable the RGB by a key-bind in ZMK, although now it turns off only the power to your RGB, and the nice!view displays stays powered, showing you battery and connection status at all times.

A powerswitch that allows you to charge the battery when powered off. The power switch isn't actually a battery disconnect in the true sense, as it instead keeps the controller in a 'powered off' mode, regardless of whether the USB power is plugged in or not, and it still allows the battery to charge if the keyboard is plugged in to a computer or charger.

Lotus 58 - BLE can be built as a DIY-kit from components or bought mostly finished, and is delivered as a semi populated PCB with all the smaller SMD components already soldered from factory, to either be finished to your own preference by soldering the larger and relatively speaking 'simpler' parts yourself like the controller module³, hotswap sockets, the display/encoder and RGB. Or, you can select to have it pre-soldered as a fairly barebones, but ready to use keyboard (No RGB/Encoder/nice!view installed), ready to flash with your preffered keymap.

Or if you prefer to avoid soldering completely and want some of the optional extras installed out of the box, you can choose to have it fully built to your specification.

Lotus 58 - BLE

Main Features:

• Features 58 keys, with a 4x6 main matrix and 4+1 thumb-keys per hand (56 normal keys with encoders installed on both hands).
• Supports up to one Rotary encoder and one nice!view display per hand.
• Designed with a Sandwich-style plate/case as part of the design and with 3D printed cases as added options.
• Fully ZMK compatible, with every aspect of it being programmable.
• Kaihl Hot-swap sockets for Cherry MX compatible switches.&#8308
• Nordic nRF52840 chipset, with 1MB Flash & 256KB RAM.
  • USB-C connector to host computer, (USB 2.0 device).
  • Low-power sleep and dormant modes.
  • Drag-and-drop programming using mass storage over USB.
• Ti BQ24075R battery charger, 4.2V Lithium @ 100/500mA rate.
  • Power Path, charges the battery as optimal even when the keyboard is used.
  • Supports a 120-750 mAh size battery per hand - Please use ZMK Power-profiler to calculate your expected battery time.⁵
  • Can be built with a pigtail battery connector for easy battery installation. (Standard JST connector).

Build Features:

• Main SMD components are delivered fully soldered, with larger and easier to solder components optionally as DIY, or fully soldered as per your preference. (Some prior soldering experience is prefferable, but not neccesary)
• The PCB design is reversible, making the PCB for both hands identical for a much lower cost.

Optional Features:

These options require additional parts

• Optional nice!view Memory-in-Pixel LCD Screen
• Optional Rotary Encoder
• Optional RGB Glow - 6 LED's per hand, aimed down.
• Optional Per key RGB - One RGB per key, lighting the key housing and keycaps if shine-through/RGB type is used.

Read more about RGB support in ZMK

Physical dimensions:

Dimensions per hand (LxBxH): 145x115 mm Case height 11-13mm, Height with keycaps/encoder ~35mm

Basic Components

Parts included in the DIY-kit:

What do you need to buy?

You can buy most parts for a full functioning keyboard in this listing or as additional components in this store. You will however need to add switches, key-caps and colored/sleeved charging cables of your choice from other sources, as it would be impossible for me to stock a reasonable selection of what the market can offer.

I however DO NOT, sell LiPO batteries. This is since shipping them to various parts of the globe as a small, one man operation with limited volume, is entirely un-economical both for me as the seller, and for you as the customer, as it requires a fair bit of hassle with various customs regulations etc. taking time that I then have to add onto the price. And I simply cannot keep the volume up enough to make the price competetive in the first place, so you are far better off sourcing this on your own.

For a bare minimum functional keyboard you will need:

• This PCB Kit (Sold as a pair)
• Case Kit (x2) with hardware or a 3D printed case or similar

Required Accessories

• Key Switches, Cherry MX compatible (56-58 pcs)
• Key Caps, Cherry MX compatible (Set)
• LiPo 3.7V nominal voltage (4.2V fully charged) battery 120-750mAh (2 pcs)
• USB cable to your computer for charging (USB type C to USB type C/A)

The Sandwich Case

Lotus 58 is designed as a complete keyboard with a sandwich style case of the same FR4 fibreglass material as the PCB.

The FR4 fibreglass plates used are quite stiff and give a good intermediate feel for keyboards, making it the ideal low cost material for a case. The 'case plates' are available in black or white, with multiple options based on your choice of layout.

Please Note! You do infact need a case of some kind, as being hot-swap compatible the front plate helps hold the switches in place, and without the plate, they will very easily come undone. You can however 3D print your own case, or have plates made in whatever material you desire. All the information required for this can be found on the linked GitHub page.

Specific caveat for Lotus 58 - unWired & BLE: These products should not be used with a metal case (both ferrous and non-ferrous metal, ie Aluminium), either CNC machined or as plates, as it reduces wireless performance and increases battery consumption noticeably.

Build Level

DIY Kit

This one is fairly obvious. You get a pair of PCB with the smaller SMD components already soldered and tested, and you solder all the larger parts like the USB port and hot swap sockets yourself, and you need to flash the needed boot loader for the modules. Note that this requires you to have a hardware device³ to flash the boot loader for the modules. Soldering the modules are slightly more advanced than I'd recommend for a complete novice, but if you have just some experience soldering from before, it is not difficult, just slightly time consuming.

Partially Built

If you do want to build most of the keyboard yourself, but are either a novice at soldering or unsure and want a little help. Or, in this case, if you simply do not want to purchase the additional hardware device to flash the boot loader. With this option, the wireless modules and the USB port are soldered and the modules flashed with the boot loader needed to flash over USB. You still need to solder most larger parts of the keyboard yourself, but the difficult parts are already done.

Fully Built

This option allows you to have a fully built, ready-to-use keyboard, where you simply need to configure the firmware (ZMK) and assemble the case/keys/caps you have chosen to start using it. This option includes soldering any extra components like encoders if included with the purchase. Note that the encoders are a separate product, and this price do NOT include them.

Pre-order

This product will initially be sold by a pre-order campaigns, with the remaining overstock from each campaign being sold as a limited stock.

What do you mean by 'overstock' and limited stock?

I need to order the blank PCB's in multiples of 5 from the manufacturer, and a pair is needed for each keyboard, so 10 PCB's or 5 keyboards is the logical batch size. Meaning that for every multiple of five keyboards after the first five which is started on the pre-order, I need to order a larger batch of PCB's to be able to fill the orders, even if I only need some of those PCB's for the actual orders sold.

This means that if the pre-order stops at for example 6-9 keyboards, there are now overstock, meaning keyboards that I have to buy parts for, but I'm not delivering to a customer and getting paid for right now. It also means that if I through the campaign manage to order a larger batch of the wireless module, I have the modules on hand to finish them and sell them as 'stocked' until I would need to order either more PCB's or modules.

This overstock will be sold at slightly higher price then the pre-order price, making me some profit for keeping stock, and also giving an incentive for you the customer to support the pre-order.

¹ You do however get one optional encoder postion less, as the wireless controller sits exactly where that was.

² While the nice!view remains always powered, because of the Sharp MIP technology, it only uses power as it's image is actively refreshed, and then only typically ~10μA, making it incredibly power efficient, but lacking 'backlight' and relying on reflective light.

³ Segger J-Link - For the full DIY option, flashing the boot loader to the modules requires a Segger J-link or equivalent hardware flasher.

⁴ Please note that Lotus supports only Cherry MX type switches (3 & 5 pin), NOT Kaihl Choc, as they require a different PCB design.

⁵ Set as 'Custom board', check 'Split Keyboard', 'Switching PSU', and other settings as default, and add your battery size, nice!view and RGB as desired.

Normal handling time is 3 - 5 working days, not including build items (Those usually take 1 - 2 weeks).

Shipping is done with insured/signed for parcels, where no such service is available the parcel is sent as insured parcel, but may not be fully traceable the entire transit. If no insured or traceable service is available, parcels will be sent as uninsured/untraceable at the buyers responsibility. All of which is clearly stated on checkout.

All packets are represented to courier services and customs at their true sale value, and all responsibility for import fees, taxes and tariffs lie with the buyer.

The SE/EU "Act on Distance Contracts and Off-Premises Contracts (SFS 2005:59)" allows returns of the items in undamaged (unsoldered!) condition within 14 days of receiving it. Return shipping on returned items are the responsibility of the buyer.