Greg
@gregdavill.bsky.social
ASIC/FPGA/PCB/FW engineer at ASTC 🧙♂️ (He/Him)
I also take macro photos of electronics
I also take macro photos of electronics
Pinned
Greg
@gregdavill.bsky.social
· Nov 21
Hi 👋
I'm Greg, hardware engineer. I enjoy designing and building open source hardware projects. along with taking macro photos to document the process.
Previously at a startup I used FPGAs and thermal LWIR cameras to map bushfires from aircraft
Currently doing RISC-V ASIC things at IQonIC Works
I'm Greg, hardware engineer. I enjoy designing and building open source hardware projects. along with taking macro photos to document the process.
Previously at a startup I used FPGAs and thermal LWIR cameras to map bushfires from aircraft
Currently doing RISC-V ASIC things at IQonIC Works
I'd forgotten that the ECP5-25F doesn't have all the I/O, and 4 or so pins that are on the 45/85F are N/C on the 25F. I just happened to use one of these for the ULPI interface. 🥲
Bodge wire to the rescue! Now we're enumerating again!
USB boot loader in gateware, takes up ~15% of the device
Bodge wire to the rescue! Now we're enumerating again!
USB boot loader in gateware, takes up ~15% of the device
September 2, 2025 at 12:30 PM
I'd forgotten that the ECP5-25F doesn't have all the I/O, and 4 or so pins that are on the 45/85F are N/C on the 25F. I just happened to use one of these for the ULPI interface. 🥲
Bodge wire to the rescue! Now we're enumerating again!
USB boot loader in gateware, takes up ~15% of the device
Bodge wire to the rescue! Now we're enumerating again!
USB boot loader in gateware, takes up ~15% of the device
These two boards have the same BGA geometry defined in their gerbers. For some reason JLCs DFM adjustments have expanded all the "via in pad" connections.
Makes for an interesting visual effect.
Makes for an interesting visual effect.
September 1, 2025 at 12:55 PM
These two boards have the same BGA geometry defined in their gerbers. For some reason JLCs DFM adjustments have expanded all the "via in pad" connections.
Makes for an interesting visual effect.
Makes for an interesting visual effect.
How's my solder paste application?
I think I missed some spots. 🫣
I think I missed some spots. 🫣
September 1, 2025 at 11:32 AM
How's my solder paste application?
I think I missed some spots. 🫣
I think I missed some spots. 🫣
FPGAs programming FPGAs 🐢
August 23, 2025 at 2:53 AM
FPGAs programming FPGAs 🐢
Plan vs. Execution
The messier the plan the cleaner the bodge looks in comparison. 😅
The messier the plan the cleaner the bodge looks in comparison. 😅
August 16, 2025 at 11:26 PM
Plan vs. Execution
The messier the plan the cleaner the bodge looks in comparison. 😅
The messier the plan the cleaner the bodge looks in comparison. 😅
Can't recall where this came from, but ended up in my labs cable drawer. Curious why it wouldn't enumerate.. 🤮
August 14, 2025 at 6:36 AM
Can't recall where this came from, but ended up in my labs cable drawer. Curious why it wouldn't enumerate.. 🤮
I've been using KiCad 9's new table features to aid in schematic documentation.
I guess it makes sense.. But still puzzled me for a moment that you can perform a vertical/horizontal mirror on a single cell. 🙃
I guess it makes sense.. But still puzzled me for a moment that you can perform a vertical/horizontal mirror on a single cell. 🙃
May 31, 2025 at 1:50 AM
I've been using KiCad 9's new table features to aid in schematic documentation.
I guess it makes sense.. But still puzzled me for a moment that you can perform a vertical/horizontal mirror on a single cell. 🙃
I guess it makes sense.. But still puzzled me for a moment that you can perform a vertical/horizontal mirror on a single cell. 🙃
Whoops, it's quick and easy to simply base 3d geometry off a KiCad board outline. But the topology has caught up to me. 🫠
May 10, 2025 at 6:13 AM
Whoops, it's quick and easy to simply base 3d geometry off a KiCad board outline. But the topology has caught up to me. 🫠
Designed this board years ago, and finally ordered it. The pattern looks really cool on the physical boards.
github.com/gregdavill/a...
github.com/gregdavill/a...
April 30, 2025 at 10:08 AM
Designed this board years ago, and finally ordered it. The pattern looks really cool on the physical boards.
github.com/gregdavill/a...
github.com/gregdavill/a...
Had an idea, and I nerd-sniped myself into building it...
Similar idea to the last ecpbreaker design, but adding the 5Gbps SERDES to enable USB3. The ECP5's serdes supports display-port, so you could probably do some cool alt-mode stuff, but currently only routed for SS USB.
Similar idea to the last ecpbreaker design, but adding the 5Gbps SERDES to enable USB3. The ECP5's serdes supports display-port, so you could probably do some cool alt-mode stuff, but currently only routed for SS USB.
April 23, 2025 at 12:54 PM
Had an idea, and I nerd-sniped myself into building it...
Similar idea to the last ecpbreaker design, but adding the 5Gbps SERDES to enable USB3. The ECP5's serdes supports display-port, so you could probably do some cool alt-mode stuff, but currently only routed for SS USB.
Similar idea to the last ecpbreaker design, but adding the 5Gbps SERDES to enable USB3. The ECP5's serdes supports display-port, so you could probably do some cool alt-mode stuff, but currently only routed for SS USB.
Spun up a new design to add an ESP32-C3 module to the back of the flip-dot module, along with DC power input.
Got a little carried away in inkscape for the silkscreen.
Trying out github.com/30350n/pcb2b..., a plugin that is in the KiCad PCM for exporting textures directly into blender, works great
Got a little carried away in inkscape for the silkscreen.
Trying out github.com/30350n/pcb2b..., a plugin that is in the KiCad PCM for exporting textures directly into blender, works great
April 21, 2025 at 4:30 AM
Spun up a new design to add an ESP32-C3 module to the back of the flip-dot module, along with DC power input.
Got a little carried away in inkscape for the silkscreen.
Trying out github.com/30350n/pcb2b..., a plugin that is in the KiCad PCM for exporting textures directly into blender, works great
Got a little carried away in inkscape for the silkscreen.
Trying out github.com/30350n/pcb2b..., a plugin that is in the KiCad PCM for exporting textures directly into blender, works great
Turns out if your riscv code causes an exception before the handler is configured and the core triggers a load access exception, you’ll be in a loop that never exits. Apologies for creating… checks notes… 1.8TB trace logs 😵💫🫢
April 18, 2025 at 2:15 AM
Turns out if your riscv code causes an exception before the handler is configured and the core triggers a load access exception, you’ll be in a loop that never exits. Apologies for creating… checks notes… 1.8TB trace logs 😵💫🫢
When you don't have the exact part... Just place a parallel combination 🙃
April 5, 2025 at 10:09 AM
When you don't have the exact part... Just place a parallel combination 🙃
When you realise that one method of creating a 32.768kHz crystal is literally just a miniature tuning fork structure.
MEMs oscillators do this to, but at another level of miniaturisation.
The lid of this one is glass and you can see that it's been laser-trimmed through likely through the window
MEMs oscillators do this to, but at another level of miniaturisation.
The lid of this one is glass and you can see that it's been laser-trimmed through likely through the window
April 4, 2025 at 11:34 PM
When you realise that one method of creating a 32.768kHz crystal is literally just a miniature tuning fork structure.
MEMs oscillators do this to, but at another level of miniaturisation.
The lid of this one is glass and you can see that it's been laser-trimmed through likely through the window
MEMs oscillators do this to, but at another level of miniaturisation.
The lid of this one is glass and you can see that it's been laser-trimmed through likely through the window
One of the joysticks on this PS5 controller had gotten really crunchy. (I think some sand made it into the mechanism scratching it up.
Picked up a few new hall-effect based joysticks to fix the controller
Picked up a few new hall-effect based joysticks to fix the controller
April 2, 2025 at 11:05 AM
One of the joysticks on this PS5 controller had gotten really crunchy. (I think some sand made it into the mechanism scratching it up.
Picked up a few new hall-effect based joysticks to fix the controller
Picked up a few new hall-effect based joysticks to fix the controller
Cool that they leave the back open on this USB-C connectors on the PS5's controller board.
April 2, 2025 at 10:55 AM
Cool that they leave the back open on this USB-C connectors on the PS5's controller board.
Sunday solderpaste stencilling
March 24, 2025 at 10:30 AM
Sunday solderpaste stencilling
Importing an image into KiCad isn't a new feature. But it's super handy for reverse engineering a design. 🐍
Would be handy if it was a touch easier to calibrate the exact image size I just adjusted scale until parts started lining up, then locked the image.
Would be handy if it was a touch easier to calibrate the exact image size I just adjusted scale until parts started lining up, then locked the image.
March 16, 2025 at 5:37 AM
Importing an image into KiCad isn't a new feature. But it's super handy for reverse engineering a design. 🐍
Would be handy if it was a touch easier to calibrate the exact image size I just adjusted scale until parts started lining up, then locked the image.
Would be handy if it was a touch easier to calibrate the exact image size I just adjusted scale until parts started lining up, then locked the image.
Added logging of dishwasher cycle count to home assistant, via an ESPHome based UART bus sniffer. Convenience factor of the top drawer being easier to fill and empty is visible in the data.
March 2, 2025 at 11:08 AM
Added logging of dishwasher cycle count to home assistant, via an ESPHome based UART bus sniffer. Convenience factor of the top drawer being easier to fill and empty is visible in the data.
I've had the flipdot bare modules for ages. And designed a few drivers, but definitely over complicated them.
This is now just shift registers + h-bridge drivers. Can't get much simplier.
This is now just shift registers + h-bridge drivers. Can't get much simplier.
February 16, 2025 at 8:51 AM
I've had the flipdot bare modules for ages. And designed a few drivers, but definitely over complicated them.
This is now just shift registers + h-bridge drivers. Can't get much simplier.
This is now just shift registers + h-bridge drivers. Can't get much simplier.
Spun up a new prototype of my LED controller. This is a minimal ESP32-C3 breakout for running esphome/wled projects.
+5-24V input.
4x Mosfet outputs for dumb LEDs
Qwicc connector for i2c/aux expansion
Extra I/O on test-points available
Low cost BOM
+5-24V input.
4x Mosfet outputs for dumb LEDs
Qwicc connector for i2c/aux expansion
Extra I/O on test-points available
Low cost BOM
February 13, 2025 at 9:44 PM
Spun up a new prototype of my LED controller. This is a minimal ESP32-C3 breakout for running esphome/wled projects.
+5-24V input.
4x Mosfet outputs for dumb LEDs
Qwicc connector for i2c/aux expansion
Extra I/O on test-points available
Low cost BOM
+5-24V input.
4x Mosfet outputs for dumb LEDs
Qwicc connector for i2c/aux expansion
Extra I/O on test-points available
Low cost BOM
