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[UnexpectedBomb]

Hi all,

I've been wishing I could get eyes on my MDD CPU temp for a long time, always worrying that it could be cooking without me knowing it, so I began working on a little side project that, to my knowledge, didn't previously exist: a Control Strip module that shows live CPU and case temperature under Mac OS 9 on the G4 MDD, reading straight from the machine's real hardware sensors.

https://github.com/UnexpectedBomb/MacOS9-G4-CPU-Temp

I was aware of a similar CSM existing in "Jeremy's CSM Bundle" but that one reads the PowerPC's on-chip Thermal Assist Unit (TAU). Motorola disabled the TAU on the 7450/7455 family, so on an MDD (and other Apollo-based G4s) it can't give you a real reading at all. This module ignores the TAU entirely and talks over the Uni-N / "KeyWest" I²C bus to the same chips Apple's firmware uses:

- DS1775 digital thermometer to get CPU temperature (within 0.5 °C accuracy, vs the TAU's ±12 °C spec)
- ADM1030 fan controller's local sensor to get case temperature

What it does:

- Shows CPU or case temperature right in the Control Strip, updating every couple of seconds
- Click the tile for a menu: pick the reading (CPU / Case) and the units (°F / °C) as two independent groups
- Text turns red as the CPU approaches its safe limit
- A Notification Manager alert pops up if the CPU ever exceeds the safe threshold (latched — it warns once, not in a loop) to prevent your CPU(s) from getting extra toasty
- Native look: bold text, fixed-width cell, custom Control-Strip-style icon
- Loads silently at startup like any stock module

It is strictly read-only on the hardware. It only reads the sensor temperature registers as an SMBus master. It never writes a sensor, fan, or config register, so it can't interfere with the ADM1030's automatic fan control. (I did try to add a fan-RPM readout, but that requires enabling the ADM1030's tachometer via a config write, and on my machine that audibly disturbed the fan... it was very angry with me... so I dropped it. Not worth frying anything!)

Give it a test-drive and let me know your experience; hopefully it gives you sane readings. I haven't tested on anything other than my MDD (FW400) so if there's other models it's compatible with, please let me know what hardware you used and how it went.

This was developed in parallel with another Mac OS 9 effort of mine, one that I think will be very exciting once it's done... you should be hearing about it hopefully later this month 

-UB

[GaryN]

I've been wishing for this for years.
I'll try it on my 2003 MDD with Sonnet MDX 2x1.8 Ghz.
I'll report back.

[GaryN]

So… I may just be getting old and senile, but I cannot, for the life of me, successfully un-bin the file in the dist folder or any other .bin file in the package with any utility I have. That includes Stuffit Expander, Stuffit Deluxe, The Unarchiver and I forget what else.

What did you use to bin them?

Please forgive me. I can't help myself… the "UnexpectedBomb" jokes just write themselves…

[UnexpectedBomb]

Hehe, I knew that username would get some laughs around here.

I cannot, for the life of me, successfully un-bin the file in the dist folder or any other .bin file in the package with any utility I have.

Sorry about that. It was a bug on my end. The .bin files were built by my cross-compiler toolchain, which writes a MacBinary header with a CRC that stricter decoders (Stuffit, Unarchiver) reject. I re-encoded the .bin as proper MacBinary II, and added a BinHex version (.hqx) as an alternative. Try now.

[IIO]

i´ve made a max app (and vst plug-in) long ago (using a driver by somebody else) which does that, but which for some reason only works on half of my computers.

i understand that most apple computers did not have digital thermometers at that time, but i dont understand why one G4-867 reports it and another G4-867 (with the same model number) does not?

[joevt]

i´ve made a max app (and vst plug-in) long ago (using a driver by somebody else) which does that, but which for some reason only works on half of my computers.

i understand that most apple computers did not have digital thermometers at that time, but i dont understand why one G4-867 reports it and another G4-867 (with the same model number) does not?

Might be a bug in your code. Use Open Firmware to access the I2C to see if it reports it?