Possible comparison of Teensy's and Apollo Moon Landing Computer??

[Matadormac]

As one who once carried a slide rule (on my belt, oh yes) and remembers Sputnik and the whole space race, I have marveled at the continued evolution of electronic computation (I once built a simple analogue computing device). I have been developing first with Arduino Unos, then Dues and now the Teensy 3.2 line of microcontrollers. I remain amazed and feel extremely beholding to the whole PJRC team for what they make it possible for me to do!

I am also interested in the history of technology and being in the museum and anthropology fields like to have convenient "yardsticks" to both illustrate and to measure such development over time.

I would really like to have a chart or spread sheet illustrating the current Teensy line as compared to a convenient benchmark such as the computer built for the Apollo lunar missions. I think this could be a good educational tool and perhaps even a convenient marketing tool for PJRC. While I could measure and weight the current Teensy 3.2 I don't know how to begin to compare the real hardware or the computing power in any terms that might make sense to a school age child or an interested but uninformed parent.

Here is an URL describing that computer project: https://en.wikipedia.org/wiki/Apollo_Guidance_Computer

And from that site this basic information:
Apollo Guidance Computer
Apollo Guidance Computer and DSKY
Invented by Charles Stark Draper Laboratory
Manufacturer Raytheon
Introduced August 1966; 50 years ago
Discontinued July 1975; 41 years ago
Type Avionics
Guidance Computer
Processor Discrete IC RTL based
Frequency 2.048 MHz
Memory 16-bit word length,
2048 words RAM (magnetic core memory), 36,864 words ROM (core rope memory)
Ports DSKY, IMU, Hand Controller, Rendezvous Radar (CM), Landing Radar (LM), Telemetry Receiver, Engine Command, Reaction Control System
Power consumption 55 W[1]:120
Weight 70 lb (32 kg)
Dimensions 24×12.5×6.5 inches (61×32×17 cm)

 

[Ben]

A comparison in computing power between two computing systems is possible in many different ways. You could look at the technical specs like how much RAM is available, how fast is the CPU, how wide are internal busses, ..., but that won't give you a good comparison of actual system performance, because there is no simple relationship between these specs and actual performance. That's why most times benchmarks are used, programs that put the system under a mix of different "typical" workloads to measure performance. Thats how the standard indicator for todays systems, the amount of FLOPS (Floating point operations per second), is generated.
I know this doesn't really answer your question, I just want to give a little background on why there is no simple answer to comparing computers unless you very clearly specify the task the systems shall perform.

 

[JWScotSat]

If anything, these kind of comparisons make me marvel at just how impressive the engineers of the 60s and 70s were. They were truly ground breaking in everything they did. The technical difficulties in creating the Apollo's computer systems must have been astounding, especially from a manufacture perspective. It seems you could make some very simple comparisons in terms of physical specifications.

Power Consumption:
Teensy ~0.2W (Based On ~40mA)
Apollo - 55W

Weight, dimensions could also be compared

Direct frequency comparison
Teensy - 96MHz without overclocking
Apollo - 2MHz

Memory Comparison
Teensy - Flash 256Kb
Apollo - 2048 Words (is that comparible to bytes? so 2Kb?)

Ram Comparison
Teensy - 64Kb
Apollo - 36Kb

Teensy Spec

These simple comparisons show that in "technical spec" the teensy far outclasses the Apollo computer. And that doesn't even cover cost!

 

[GremlinWrangler]

Also don't forget those numbers above include the screen and keyboard (albeit a very special one). So you need to either need to compare the Teensy CPU with the AGC computer core or compare a Teensy built out as a working guidance computer with interface to navigation aids, user interface etc.

Also missing is the fact that a Teensy is in no way radiation hardened.

A possibly more interesting question (though even harder to find the answer for) is 'at what point did NASA own less ground based computing power than found in a Teensy'.

 

[Ben]

Memory Comparison
Teensy - Flash 256Kb
Apollo - 2048 Words (is that comparible to bytes? so 2Kb?)

Ram Comparison
Teensy - 64Kb
Apollo - 36Kb

I think you mixed something up. Or maybe I did, anyway, I get different numbers:
Apollo RAM: 2048 x 16bit = 32768 bit = 4096 Byte = 4kBytes
Teensy RAM: 64 kBytes
Apollo ROM (Program Memory): 36864 x 16bit = 589824bit = 73728 Byte = 73kByte
Teensy ROM: 256 kBytes

 

[JWScotSat]

I think you mixed something up. Or maybe I did, anyway, I get different numbers:
Apollo RAM: 2048 x 16bit = 32768 bit = 4096 Byte = 4kBytes
Teensy RAM: 64 kBytes
Apollo ROM (Program Memory): 36864 x 16bit = 589824bit = 73728 Byte = 73kByte
Teensy ROM: 256 kBytes

Yeah that's probably correct. I didn't factor the word -> conversion

 

[tni]

Direct frequency comparison
Teensy - 96MHz without overclocking
Apollo - 2MHz

That's quite misleading. The Apollo has a limited instruction set and needs at least 12 clock cycles to execute an instruction (Teensy can execute most instructions in 1 clock cycle). It's also 16-bits only. You can expect a Teensy to be at least 1000x faster.

A good comparison would be a TI-81 calculator (released 1990), which has a Z80 CPU running at 2MHz.

 

[adrian]

would the Apollo AGC make a good midi controller?

 

[defragster]

Just saw this :: Apollo-11-Computer-vs-USB-C-chargers.html

Apollo 11 Guidance Computer (AGC) vs USB-C Chargers
I think it is healthy to compare historical and modern computing. Let's see how the CPUs contained in recent USB-C wall chargers compare to the power of the Apollo 11 Guidance Computer (AGC). The Apollo 11 spacecraft carried 3 humans to the moon and back in 1969.

…

The Anker PowerPort Atom PD 2 USB-C Wall Charger CPU is 563 times faster than the Apollo 11 Guidance Computer.

563 = (12 Cortex-M0 instructions per 1 Apollo 11 Guidance Computer instruction) * (48 MHz Cortex-M0) / (1.024 MHz Apollo 11 Guidance Computer).
After skimming though the Apollo 11 Guidance Computer instruction set, the only important missing Cortex-M0 instruction seems to be division. But each division on the Apollo 11 Guidance Computer takes 72 cycles * (1/1.024MHz) = 70.3 uS. In 70.3uS the CYPD4225 can execute 70.3uS * 48 MHz = 3374 arithmetic instructions. Branches are not too expensive (3 cycles). Hopefully that is enough to implement software division.