transistor fet
LightNews LightNews
banner
transistorfet.bsky.social
transistor fet
@transistorfet.bsky.social
140 followers 240 following 40 posts
a queer trans autistic mentally ill enhancement mode complimentary metal oxide semiconductor field effect transistor... also a cat, (a meowsfet)

https://jabberwocky.ca
https://github.com/transistorfet
https://linktr.ee/transistorfet
Posts Replies Media Videos
transistorfet.bsky.social
It's working now, and the k30p CPU card can talk to it! I only put one 1MB RAM chip on for now, but I can put the others on now that I know it's working
The fully assembled and unplugged MemBird Woodcock Memory Card, with red solder mask, white silkscreen text, and a big greyish-white DIN41612 connector on the right side. A silkscreen picture of an American Woodcock bird is near the top.
January 4, 2025 at 5:28 AM
transistorfet.bsky.social
The assembled board
An almost fully assembled PCB of the k30p-VME card, with purple solder mask and white silkscreen labels, with a large PGA version of the 68030 in the centre and a PLCC 68681 serial controller to the left. Some bodge wires are visible on the SMT transceivers down the right side. The VME connector on the right is not installed and some leds, buttons, and ftdi on the left are missing, but everything else is populated. It's sitting on a thin block of pine wood, with a 10 pin ribbon cable attached near the bottom, a purple USB-C cable conected on the left, and some black and white Dupont wires and a white alligator clip in the bottom right. A black oscilloscope probe with a yellow identifying ring and red scale select switch is just visible in the top left.
December 23, 2024 at 1:24 AM
transistorfet.bsky.social
Some success! The CPU is running the monitor rom. It prints out the welcome message, and it seems to be running for long enough to type some things at the prompt, but then it seems to reset itself after a few seconds and repeat. Not sure what's causing the reset yet, but this is progress!
A screenshot of a terminal program with a dark space photo as the background and white text showing the message "Welcome to the 68k Monitor!" followed by two newlines and then the "> " prompt. The message and prompt repeat 4 times in total, with the third time showing some typing at the prompt, specifically "oeuioeuioeuioeuioeuioeui"
December 23, 2024 at 1:12 AM
transistorfet.bsky.social
I'm going to build the MC68030 board on stream shortly (~12PST) at www.twitch.tv/transistorfet
A bare PCB of the k30p-VME CPU card, with purple solder mask, white silkscreen labels, and silver pads. It says "k30p-VME Rev. 1" at the top centre, and "Designed by transistor fet October 2024" in the middle of the board
December 15, 2024 at 7:20 PM
transistorfet.bsky.social
My Christmas projects arrived ❤️
A picture of four stacks of PCBs on a pine-coloured desk. Two of the boards are 100mm x 160mm, one in green solder mask that says "COMET / Compact Flash Interface / Tom Storey Mar 2024 Rev 2B" along the bottom with a stylized image of a comet, and the other in purple solder mask that says "k30p-VME Rev. 1" along the top and "Designed by transistor fet October 2024" off centre near the middle. There is also a red PCB below that, which says "MemBird Woodcock Rev. 1" along the top with a stylized image of an American Woodcock. Next to it, at an angle, is a stack of narrow aluminum PCBs 20mm x 128mm with white solder mask and black silkscreen that will be the frontpanel for the purple board, which says "CompuieVME" along the top, with cutouts and labels above them for the LEDs, buttons, and USB ports on the edge of the card.
December 11, 2024 at 2:32 AM
transistorfet.bsky.social
I figured I should put something on the unused space on the back, so I took inspiration from your comment and put 🥺
The close-up of the back of a PCB with red solder mask, and a white silkscreen image of the pleading face emoji 🥺
December 11, 2024 at 2:22 AM
transistorfet.bsky.social
The printed boards have arrived
A stack of unassembled PCBs with red solder mask, and white silkscreen labels that says "MemBird Woodcock Rev. 1" along the top, with a silkscreen image of the outline of an American Woodcock bird walking.
December 11, 2024 at 2:16 AM
transistorfet.bsky.social
It's finished! I'll probably tweak it a bit more over the coming days, and order it along with two other boards early next week so they arrive by the 13th when my vacation starts
A screenshot of KiCad's PCB editor with the finished design for MemBird - Woodcock, a 16-bit VME memory card. The board is square at 100mm x 100mm. A silkscreen label at the top of the board reads "MemBind Woodcock Rev. 1" and just below that to the right is a silkscreen outline of an American Woodcock bird with one leg raised forward as if it were walking on the ground. It almost appears to be standing on a dashed line box just below it for the optional circuitry. Red lines representing the front side copper of the board run left to right, and blue lines representing the back side copper of the board run up and down. A large VME bus connector runs the length of the board on the right side.
December 1, 2024 at 5:59 AM
transistorfet.bsky.social
I think I have the logic correct, but maybe it's possible to optimize it further for part count/type
A screenshot of a schematic diagram in KiCad, with the Vampire theme of magenta and green lines and blue text on a deep purple background. It shows the logic needed to connect the VME bus signals to one of four 512K x 16 bit SRAM chips (not shown), and control the address and data transceivers (not shown), which are used as level converters between the 5V bus voltage and either 5V or 3.3V memory voltage
November 26, 2024 at 5:41 AM
transistorfet.bsky.social
I'm going to stream the design of a memory card for my computer project, now and over the weekend. www.twitch.tv/transistorfet
A scrap piece of paper with pencil drawings and notes with the title MemBird - Woodcock? Timberdoodle? with some high-level schematics showing the plan, and some notes: - ASa, AM, Address with comparator to derive board CS - DS, LWORD - drive DTACK from a timer? - for 16-bit operation, you could assert BERR if LWORD is low or AM is not valid but the address is
November 23, 2024 at 10:52 PM
transistorfet.bsky.social
I grew a flower on my patio
A medium-sized flower with thin bright orange petals and a black centre, grown from seeds labelled Venidium Orange Prince
August 2, 2024 at 6:14 AM
transistorfet.bsky.social
The LED was my error (I was using the wrong I/O). So with that working, I soldered the ethernet interface up, and tested it with the ping example from the Rust STM32H7xx HAL, and it worked first try! I've got it almost fully populated now. Now to experiment with the VME bus
January 8, 2024 at 2:54 AM
transistorfet.bsky.social
Well it's not *not* working. I can program the chip, and it seems to sometimes print the debug messages, but the LEDs don't light as expected, the debugger often can't find the rtt block, and after pressing the reset button it can't even be programmed unless it's power cycled
January 7, 2024 at 6:10 AM
transistorfet.bsky.social
My latest boards arrived just in time for the weekend!
A blue printed circuit board with a silkscreen picture of Bronson the Cat and the text "Big Boy Rev. 1"
January 5, 2024 at 10:26 PM