For this project, I decided to design a small 4-key macropad combined with an alarm clock. The device is called WakePad and it is designed for my younger brother. The idea is to make something useful and fun: a small desktop device that can show the time, allow the user to set an alarm, and use four mechanical keys for controlling the clock and alarm settings.
PCB Layout
I started the PCB layout in KiCad PCB Editor.
The design direction was changed from a 2×2 button layout to a horizontal layout inspired by compact screen macropads.
The current physical layout is:
Top area: empty space reserved for OLED screenMiddle: four mechanical switches in one rowBottom: XIAO microcontroller, OLED connector, RTC connector, and buzzer connector
The button row is arranged like this:
[ SW1 ] [ SW2 ] [ SW3 ] [ SW4 ] MODE SET UP DOWN
The switch spacing was planned around the standard keyboard spacing:
19.05 mm center-to-center
This gives the keys a compact keyboard-like appearance, similar to the reference macropad images.
Board Outline
I created an Edge.Cuts outline around the PCB.
The outline was made wide enough for:
The four switchesThe XIAO microcontrollerThe OLED/RTC/buzzer connectorsA screen area above the buttons
The board currently has a wide horizontal shape, matching the style of the reference design.
PCB Routing
I started routing the PCB traces.
Most of the connections have been routed on the front copper layer:
F.Cu
The routed connections include most of the switch, OLED, RTC, buzzer, power, and signal connections.
At the current stage, the PCB is almost fully routed, but there are still a few remaining unrouted connections.
The current status shown in KiCad is:
Unrouted: 4
This means four connections still need to be completed before the PCB is electrically finished.
Current Status
So far, the project has completed these stages:
Project idea selectedSchematic createdMain components addedSwitches, OLED, RTC, and buzzer connectedFootprints assignedPCB layout startedHorizontal 4-key layout createdBoard outline drawnMost traces routed
The project is now in the final part of PCB routing.
Next Steps
The next tasks are:
Finish the 4 remaining unrouted connectionsUse B.Cu and vias if neededOptionally add a GND copper zoneRun DRCFix any DRC errorsCheck the PCB in 3D ViewerPrepare for case design
After the PCB has:
Unrouted: 0
the next important step will be running:
Inspect > Design Rules Checker
The PCB should only move forward when there are no serious DRC errors.
So far, I created the schematic for WakePad, a 4-key alarm clock macropad designed for my younger brother. I added the Seeed XIAO microcontroller, four mechanical switches, a 4-pin OLED connector, a 4-pin RTC connector, and a 2-pin buzzer connector. The switches are connected to separate GPIO pins, while the OLED and RTC share the I2C SDA and SCL lines. The buzzer is connected to a GPIO pin and GND. The next step is to fix ERC warnings, assign footprints, and start the PCB layout.
