24 February 2024 - 01 March 2024

Table of Contents

1. MIT OCW

1.1. 18.06sc (Linear Algebra)

1.1.1. Unit I - Column Space and Nullspace

1.1.2. Premutation matricies

n=9 ran for 5 days with no solution and massing swapping. Started looking into Julia, partly because of distributed computing support, but AMDGPU interface fails testing, so maybe not ready for me yet.

2. wood chips

Rainy.

3. SCZ Front Step

No progress. Wet, Rainy…

4. Compilers

4.1. Compiled Wikipedia PL/0 example

4.2. Work out overall plan.

Lots of moving pieces.

4.3. Looking into LLVM MLIR.

Will not use immediately, but perhaps trend in that direction.

4.4. ASDL

4.4.1. current smlnj C++ implementation incomplete

4.4.2. old versions asdl source fail to build with new versions of smlnj

4.4.3. old versions of smlnj not easily buildable on x8664

4.4.4. ancient binary of asdl 1.2 compiler seems to work

but associated libraries are to old to link because of missing ctype symbol

4.4.5. analyzing asdl 1.2 generated code

Most of the code is for serialization, which is going to be replaced anyway, so can be removed by hand.

5. Piper dovecot

5.1. Update broke dovecot auth.

Looks PAM related, but PAM update failed to fix.

5.2. Set tuffy up as a staging server

So I don't debug on 'production'.

5.3. piper dovecot SSL certificate NOT broken

At least not obviously broken (yet). Further investigation needed.

6. Various i686

6.0.1. netbsd

installed. (but on what? - one of the old gateway boxes).

6.0.2. buildroot

builds complete.

7. piper

7.1. dovecot

7.1.1. Raising apparmor error.

Not sure how to resolve.

7.2. pidgeonhole

7.2.1. procmail replacement.

7.2.2. Considering integration.

7.3. httpd

7.3.1. Still stable.

But seems to occassionally mis-serve files.

7.4. SSL cert

Trying letsencrypt with certbot. http problem above may be interfering.

7.5. redmine

Still not sure I want to go down this rabbit hole.

7.6. openvpn

Need to consider cert construction.

8. Buffalo WZR-HP-G300NH

8.1. Update

Sometime next year.

9. SJC weather station

9.1. Proper enclosure mostly constructed

9.1.1. Needs a redo on bottom plate

9.1.2. Seems to have improved wireless connectivity somewhat

10. opencl

10.1. Studying. Have some examples working.

10.2. Need to look at arrayfire as an alternative.

10.3. This is a bit of a hammer looking for a nail.

11. EPLDH

11.1. MPFI interval arithmetic better alternative

12. wktpqb

12.1. needs a new approach

12.2. Verifying edge construction (con't.)

12.3. 'gcd' algorithm doesn't work

13. Mill Controller #2

13.1. Mounted on mill - ready or testing

13.2. Need to investigate new HW/SW for eventual replacements

13.2.1. Old crap ain't gonna last forever

13.2.2. Buildroot/Linux 5.15 PREEMPT + latency tools

First pass done - boots on real hardware

13.3. Alternative architecture

13.3.1. Split off stepper motor controller to separate board

Increase latency tolerance on controller

13.3.2. Use emc2 MODBUS/TCP protocol for stepper and other IO

14. Alum Rock Data Center

14.1. May have problem with network power module.

It's only 30 years old or something like that.

14.2. Added Ethernet card to tuffy

Preparing as backup/staging server.

14.3. Need a VPS with static IP

Maybe not. Perhaps just use dynamic interface to bind.

14.3.1. OpenVPN to tie it all together

Maybe not.

14.3.2. Gandi VPS datacenter in France so connection crosses international border

What are the data security and privacy tradeoffs?

14.3.3. Prototype VPS on existing hardware

  1. OpenStack?

15. CA Root Key Generation

Nice to have an appliance that manages keys. Need to make this simple. Really don't have time for a science project. Could just buy something from nitrokey https://www.nitrokey.com/ But I really don't want to spend money on it of I have hardware already.

15.1. First pass done

15.1.1. Based on https://pki-tutorial.readthedocs.io/en/latest/simple/

Interesting that the certs generated fail with openssl sserver testing because the cryptographic algorithms are too weak.

15.1.2. Work continues

I used to find this stuff really interesting - now it's really tedious.

15.2. Need to be clear on security properties.

Definitely protect against remote access to private keys. How strong does the protection against local access need to be?

15.3. Simple hardware.

15.3.1. Use beagleboard with local interface

15.3.2. Use some modern device TPM

Need to export data for backup.

15.3.3. Or something that uses PKCS11 interface

15.4. USB Serial interface only but no credentials across USB I/F.

But this potentially exposes the hardware to remote access via the USB I/F when connected.

15.5. Use Sneakernet

Doesn't scale. Should use something so cert updates are automatable. But that's a science project it seems.

16. Virtual Orchestra

16.1. sfz file tests

16.1.1. need tooling to edit sample files

16.2. increasingly skeptical whether quality results are possible

16.3. maybe should treat as platform for concatinative synthesis

16.4. maybe should just accept the limitations and work with it

One should not be disappointed that a guitar can't sound like a flute.

17. gat

17.1. spectrogram done - matches 'octave' output

18. RIOT drivers

Implemented - needs testing.

18.1. WS2801

18.2. Velleman KA03

18.3. Velleman KA05

19. mcd05 32 button/led box

19.1. Recovered schematics.

19.2. Planning software.

19.3. Received STM32F767 Nucleo144 with Ethernet.

19.3.1. Test program running.

19.3.2. Need to consider CoAP multicast discovery.

19.3.3. Consider simpler architecture with STM32F767 as a 'hub'.

19.3.4. Consider CAN interface to hub.

20. AMD 2900 bitslice computing

20.1. Probably my oldest uncompleted project

20.2. Exploring possibilities for something constructive

Create verilog models for 2903/2910 and verify against hardware?

21. Hitachi HD68B09E CPU

21.1. RAM/UART/IO

21.2. Started schematic

21.2.1. Standard peripheral set for 8 bit CPU bringups

Board schematic planned - need Kicad symbols

21.3. Arduino Mega 2560 DMA loader

…Along with standard 8 bit loader

21.4. Generate quadrature clock directly

21.5. Full Bus SW Emulation infeasible

6809 1000ns maximum cycle time too short

22. Rockwell R65F11

22.1. Still evaluating.

22.2. Dev board

Reverse engineered some of a mostly fully built development board with one part missing. As near as I can tell, that one part is some sort of programmable address decoder with a pinout that does not correspond to any part I can find. Kind of like a GAL but with inputs on top and outputs on bottom (as opposed to left and right in a standard GAL). I have no idea what the provenance of this board is and if it ever worked.

23. PLD programming

Looks like Atmel 16V8 is the last 5V PLD part left standing. Maybe not surprising that there still doesn't appear to be a fully open source tool chain for programming. How hard could it be? (!) Could next-pnr generic help? Might be easier to use espresso for logic array and program output logic bits directly for simple stuff.

24. EPROM Programming

Found some software for Needham programmer. Need to check electrolytic caps on ISA board.

25. POSIT

25.1. Use POSITs for YRX?

No. Existing library is fine.

26. MAME

26.1. Subset builds in debug mode

Full debug fails - not enough disk or memory.

26.2. gs6809 serial IO doesn't work right with PTY and other streams

26.3. ampro (Z80/Z80SIO) does work with PTY

26.4. Evaluating what is needed for other emulators.

27. More project ideas

27.1. Zuse Z3 simulation in Verilog

Good excuse for floating point ALU design. Try posit format?

27.2. GMPForth ports to simulators

27.2.1. SIMH for some targets (vax)

27.2.2. MAME looks interesting for microprocessor system emulations

How to support ersatz systems?

27.2.3. Ports to classic figFORTH targets

27.3. GMPASM assembler

May be useful for handbuilt and rare systems (DMX1000?).

27.4. Extracting ISO Superboard Forth ROMS for MAME emulation

27.5. 'bwocl' OpenCL tooling

27.5.1. Offline compilation

27.5.2. Standard Kernel Running

27.6. hardware support for classic 5V CPUs

27.6.1. RTX2000, CDP1802 still available!

27.6.2. 6502, 68000, 320C30, others on hand

27.6.3. CPUs with totally async bus may be supportable without RAM

27.6.4. Could use small footprint monitor in asm (gmpmon?)

27.7. Existing 'retro' hardware still working?

27.7.1. OSI Superboard

Unknown. Composite to VGA adapter didn't seem to work. Needs analysis. Found OSI model 610 board underneath!

27.7.2. Super Jolt

No output. Needs analysis.

27.7.3. Ampro Little Board

Not booting. Needs analysis.

27.7.4. Rockwell R65F11 Demo board

UART sending "NO ROM" at 2400 7N1 as expected with 2MHz xtal. MAME emulator possibilities?

27.7.5. NMIX-0016

Works. Found original prom in a parts stash(!).

28. David Davies

28.1. Broadcom BCG? Employee indicted for running a brothel.

28.2. New case C1923172, consolidated with 15 Parties.

28.3. Next hearing 2/26/2024

Author: Daniel Kelley

Created: 2024-03-09 Sat 07:05

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