binary arithmetic

OP's homework / lab assignment is to build up to the venerable 2901 series, let 'em Google it up for 'mself.

--
 JosephKK
 Gegen dummheit kampfen die Gotter Selbst, vergebens.  
  --Schiller

On 2007-01-30, Icky Thwacket wrote:

the flip-flop can be built using nands (I used 10)

here's a simulation in lt-spice

##### cut here ##### Version 4 SHEET 1 880 680 WIRE -320 32 -336 32 WIRE -224 32 -240 32 WIRE -400 48 -432 48 WIRE -176 128 -208 128 WIRE -32 128 -80 128 WIRE 112 128 64 128 WIRE 256 128 192 128 WIRE 368 128 352 128 WIRE 416 128 368 128 WIRE -240 144 -336 144 WIRE -224 144 -224 32 WIRE -224 144 -240 144 WIRE -208 144 -208 128 WIRE -208 144 -224 144 WIRE 368 144 368 128 WIRE -208 160 -208 144 WIRE -176 160 -208 160 WIRE -80 160 -80 128 WIRE -80 160 -112 160 WIRE -32 160 -64 160 WIRE 64 160 64 128 WIRE 64 160 32 160 WIRE 112 160 96 160 WIRE 192 160 192 128 WIRE 192 160 176 160 WIRE 256 160 224 160 WIRE 352 160 352 128 WIRE 352 160 320 160 WIRE 416 160 400 160 WIRE 496 160 480 160 WIRE 560 160 496 160 WIRE 96 192 96 160 WIRE 208 192 96 192 WIRE 400 192 400 160 WIRE 512 192 400 192 WIRE -288 208 -336 208 WIRE -256 208 -288 208 WIRE -208 208 -256 208 WIRE -176 208 -208 208 WIRE 192 208 192 160 WIRE 192 208 96 208 WIRE 496 208 496 160 WIRE 496 208 400 208 WIRE -208 240 -208 208 WIRE -176 240 -208 240 WIRE -64 240 -64 160 WIRE -64 240 -112 240 WIRE -32 240 -64 240 WIRE 96 240 96 208 WIRE 112 240 96 240 WIRE 224 240 224 160 WIRE 256 240 224 240 WIRE 400 240 400 208 WIRE 416 240 400 240 WIRE -240 272 -240 144 WIRE -112 272 -240 272 WIRE -32 272 -112 272 WIRE 112 272 32 272 WIRE 208 272 208 192 WIRE 208 272 176 272 WIRE 256 272 208 272 WIRE 416 272 320 272 WIRE 512 272 512 192 WIRE 512 272 480 272 WIRE 560 272 512 272 WIRE -288 288 -288 208 WIRE -432 304 -464 304 WIRE -256 320 -256 208 WIRE 224 320 224 240 WIRE 224 320 -256 320 WIRE -112 432 -112 272 WIRE 32 432 -112 432 WIRE 336 432 192 432 WIRE 512 432 416 432 WIRE -256 480 -256 320 WIRE 32 480 -256 480 WIRE 512 480 208 480 FLAG -544 304 0 FLAG -512 48 0 FLAG 368 224 0 FLAG -336 144 D IOPIN -336 144 In FLAG -336 208 clk IOPIN -336 208 In FLAG 560 272 Q_a IOPIN 560 272 Out FLAG 560 160 _Q_a IOPIN 560 160 Out FLAG 512 432 Q_f IOPIN 512 432 Out FLAG 512 480 _Q_f IOPIN 512 480 Out SYMBOL Digital\\\\and 0 80 R0 SYMATTR InstName A1 SYMBOL Digital\\\\and 144 80 R0 SYMATTR InstName A2 SYMBOL Digital\\\\and 144 192 R0 SYMATTR InstName A5 SYMBOL Digital\\\\and 0 192 R0 SYMATTR InstName A6 SYMBOL Digital\\\\and -144 80 R0 SYMATTR InstName A7 SYMBOL Digital\\\\and 288 80 R0 SYMATTR InstName A3 SYMBOL Digital\\\\and 448 80 R0 SYMATTR InstName A4 SYMBOL Digital\\\\and 448 192 R0 SYMATTR InstName A8 SYMBOL Digital\\\\and 288 192 R0 SYMATTR InstName A9 SYMBOL Digital\\\\and -144 160 R0 SYMATTR InstName A10 SYMBOL voltage -416 48 R90 WINDOW 0 -32 56 VBottom 0 WINDOW 3 32 56 VTop 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V3 SYMATTR Value SINE(.5 .6 50 0 0 90) SYMBOL voltage -448 304 R90 WINDOW 0 -32 56 VBottom 0 WINDOW 3 32 56 VTop 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value SINE(.5 .6 3000 0 0 70) SYMBOL res 352 128 R0 SYMATTR Value 10k SYMBOL Digital\\\\dflop 112 384 R0 SYMATTR InstName A11 SYMBOL voltage 320 432 R270 WINDOW 0 32 56 VTop 0 WINDOW 3 -32 56 VBottom 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value .03 SYMBOL Digital\\\\buf -400 -16 R0 SYMATTR InstName A12 SYMBOL Digital\\\\buf -432 240 R0 SYMATTR InstName A13 SYMBOL voltage -336 32 R270 WINDOW 0 32 56 VTop 0 WINDOW 3 -32 56 VBottom 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V4 SYMATTR Value .01 SYMBOL voltage -384 288 R270 WINDOW 0 32 56 VTop 0 WINDOW 3 -32 56 VBottom 0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V5 SYMATTR Value .02 TEXT -526 426 Left 0 !.tran 0 0.1 0 .0001 #### cut here ####

--

Bye.
   Jasen

Ah, the 2901. I studied their app notes, and got the idea to pipeline the character data for my TV typewriter. ;-)

Cheers! Rich

Maybe you should aks one of the newer graduates.

I hate to admit how many of those books I have owned.

The Osborne book on microcomputers was my first solid hardware tech manual, and the Leventhal book on Z80 assembly anguage my first good book on software.

[.....]

The PDP-8S, the 1802 and 8051 were all serial at the core.

There used to be a serial multiplier chip. I think it was TI. You put one number on 8 inputs and shifted two others in. What shifted out was:

Y = A*B + C

Your first computer predates mine a little.

--
--
kensmith@rahul.net   forging knowledge

No, the OP wants to multiply and divide too.

--
--
kensmith@rahul.net   forging knowledge

[...]

29116s a few 29540s and some registered PROMs can still make a nice processor if you have a cooling fan.

--
--
kensmith@rahul.net   forging knowledge

If it isn't a microprocessor they wouldn't know ;-)

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | |

| 1962 | I love to cook with wine. Sometimes I even put it in the food.

In both my US Navy technical training schools and my Discrete Mathematics course at SDSU I ws tought that you could construct any digital logic device from 2-input nand gates (or two-inout nor gates, for that matter) embedded in the training unit concerning transformations under DeMorgan's Laws.

Perhaps the syllabus at MIT hadn't formulated that principle so simply back then.

You missed the discussion where I said you could do that, but seriously skew the S/R timing.

BTW: I taught this stuff from ~1964-1968.

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

I cought the part where you said your needed a three-input nand gate, and then rapped your brass rat on the table as an appeal to authority.

And the appeal to authority continues.

I remember when the 1802 and the 8051 came out, there never was anything serial about the 1802 and only the embedded comm ports on the 8051 were serial. As for the PDP-8s i do not pretend knowlege.

--
 JosephKK
 Gegen dummheit kampfen die Gotter Selbst, vergebens.  
  --Schiller

OK, smart-ass Richard Henry... show me a COMMERCIAL version that uses just 2-in-NAND's.

For that matter, (unless it's PECL) show me a MODERN D-Flop that uses GATES at all ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

CMOS latches are often made using two inverters wired front to back with a (more powerful) gate on the data and clock feeding one end of the inverters. A couple of latches in series with an inversion in the clock and you have a DFF. They look like gates on the schematic, anyway.

--
  Keith

Keith! Keith! Keith! Keith!

Modern CMOS D-flops use so-called "transmission gates", otherwise known as analog "switches".

So there's nothing there but inverters and analog switches ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.

I saw the central processor board of a PDP-11 once - about 18" wide and 14" or so long, and it had 4X 74LS181, 3 or 4X 74LS183 carry generators, The pipeline registers, microprogram PROM, and all that nifty glue logic. At the time, I found it supremely cool, since at the time I was reading AMD's 2900 series app notes. That's where I got the idea to pipeline the character data for my TV typewriter. :-)

Cheers! Rich

ago

Not all use the "analog" switches. At low voltages, transmission gates tend to be slow and