Logic Help Please

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Gorgon
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Re: Logic Help Please

Post by Gorgon »

Hi Paul,
If I understand you correct you have reversed the inputs (IP) and the outputs(OP) in your question.

The IP0-9 (pin1-10) is all inputs, and their state reflects on all the outputs OP0-9(pin23-14).
So, if IP0 is 'on' all OPs will go 'on', since IP0 is included in all the equations. You read the equations from left to right, like a normal math equation. The '+' between the IPs indicates an 'OR' operator.

To answer the question. If pin 2 goes high pin 14-22 goes high, not 23.

I kept the order for inputs and outputs the same on both side of the chip, from top(0) to bottom(9).

TOK ;)
Gorgon the Caretaker - Character in a childrens TV-show from 1968. ;)
paulsantangelo
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Re: Logic Help Please

Post by paulsantangelo »

Hey Gorgon:

I'm sure you know, I'm having a problem understanding this.

I get that the state of the input reflect the output. IP0 goes high ALL outputs are high, (is this normal)?

Is this because of equation OP0 = IP0 or OP9 = IP0 + IP1 + IP2 + IP3 + IP4 + IP5 IP6 + IP7 + IP8 + IP9.

Thanks

paul
paulsantangelo
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Re: Logic Help Please

Post by paulsantangelo »

Ok, rethinking this, In the equations these are OR's. So because the outputs are combinatorial, they are tied together.

Since OP9 Includes all the inputs if one of them is high, then all the outputs are high.

Same with OP8, just you do not include one input.

Philba was right you are clever.

You really should write an article. On both programming eproms and PDLs!! Heres the thing, People that do the same thing day in/ day out, it becomes common place, they dont know that the thing they are doing really can benefit others, just because it so common to the individual!!

There is an article published every month in the EPE mag called Back to Basics and it basically covers CMOS. This information would be a great complement to that article.

Hope you understand
-paul
Gorgon
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Re: Logic Help Please

Post by Gorgon »

Originally posted by paulsantangelo:
Well I messed that up


Here it is again hopefully formated better

This first one we already worked on..

pin........Binary
.......Bit7......0
0.........10000011
1.........00000111
2.........00001110
3.........00011100
4.........00111000
5.........01110000
6.........11100000
7.........11000001


This is for the second chip

Pin......... Binary code
.......Bit9........0
0.........1111111111
1.........1111111110
2.........1111111100
3.........1111111000
4.........1111110000
5.........1111100000
6.........1111000000
7.........1110000000
8.........1100000000
9.........1000000000
Hi Paul,
The two GALs reflect your table above. The 'pin0-(7)9' is the same as 'IP0-(7)9' and the 'bit0-(7)9' is the same as 'OP0-(7)9'. The (7) is for gal1.

In the equations, like 'OP1 = IP0 + IP1', the OP1 equal IP0 OR IP1. In plain language, if either of the two inputs are 'on' the output is 'on'. If both are 'off' the output is 'off'. The different outputs are not connected to each other in any way, only to the '0' and '1' states of the inputs listed in the equation for that output.

I hope this is what you wanted from your table? Pleas note that you must 'turn' your tables 90 deg to the left to get the outputs to the left as in the equations.

The equation for IP0 = all OPs, is the topmost line in your table. This is because IP0 is in all the equations:

Code: Select all

OP0 = IP0
 OP1 = IP0 + IP1
 OP2 = IP0 + IP1 + IP2
 OP3 = IP0 + IP1 + IP2 + IP3
 OP4 = IP0 + IP1 + IP2 + IP3 + IP4
 OP5 = IP0 + IP1 + IP2 + IP3 + IP4 + IP5
 OP6 = IP0 + IP1 + IP2 + IP3 + IP4 + IP5 + IP6
 OP7 = IP0 + IP1 + IP2 + IP3 + IP4 + IP5 + IP6 + IP7
 OP8 = IP0 + IP1 + IP2 + IP3 + IP4 + IP5 + IP6 + IP7 + IP8
 OP9 = IP0 + IP1 + IP2 + IP3 + IP4 + IP5 + IP6 + IP7 + IP8 + IP9
TOK ;)

<small>[ November 12, 2005, 07:53 AM: Message edited by: Gorgon ]</small>
Gorgon the Caretaker - Character in a childrens TV-show from 1968. ;)
paulsantangelo
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Re: Logic Help Please

Post by paulsantangelo »

Yeah: Its kind of an IF OR statement in BASIC, neat!

If IP9 is ON then only OP9 is on.
If IP8 is on then both OP9 and OP8 are on.

I'm reading it down from the chart above. I do understand, now!

This is really different from the eprom programming we were doing earlier, hope others benefit from this also.

That looks right to me!!

Can you tell me what combinatorial means then?

Thanks again.

I hope your an instructor, if not you should be!!

-paul
Gorgon
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Re: Logic Help Please

Post by Gorgon »

Hi Paul,
Combinatorial means what the word says, combinations, or logic combinations. When programming the GAL you can use the outputs as 'combinatorial', 'registered' or 'latched'.

'Registered' is used with clocked flanks and memorize the conditions. The 'latched' outputs does also 'remember' but use level changes to retain the condition.

So, the combinatorial logic use the only the current states of the inputs through a set of logic functions like AND, OR, NOT to generate an output. Just like your equations.

No, I'm not an instructor. I work as a development engineer in both hardware and software. This I have done for 25 years now.

TOK ;)
Gorgon the Caretaker - Character in a childrens TV-show from 1968. ;)
paulsantangelo
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Re: Logic Help Please

Post by paulsantangelo »

Thanks:

I dont fully understand "Clocked flanks" but I can look into it. When I get the chips in I let you know if it works, but I'm sure you know it would. Does it matter which manufacture of chips. Lattice or ATMEL?

I noticed you did not use pin 0 for your first input. It probaby because thats for a clock, right? I saw of the net some simulators where if you send a pulse you can actually have the outout pins appear to count. It was pretty neat!

I almost wish I didn't get out of this when I was a kid. I'd know so much now, but here in Connecticut there isn't many jobs for hardware (firmware) programmers. Had to go the way of the trend!

Thanks for all, and write that article, we need it!!!

-paul
Gorgon
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Re: Logic Help Please

Post by Gorgon »

Hi Paul,
I suppose your comment on the pin0 was without deep thought. Normal chips start their pin numbering from pin 1, at least I have not seen anything else :D

And, please update us on your progress. Ask if you meet problems along the road to whatever you build.

TOK ;)
Gorgon the Caretaker - Character in a childrens TV-show from 1968. ;)
paulsantangelo
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Re: Logic Help Please

Post by paulsantangelo »

Yeah well I guess I deserved that one, I mean its not like I didn't look at the specs, just got a little confused between my inputs / output and leaves, New England ya know!

Thanks for the help. I'll let you know!

-paul
paulsantangelo
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Re: Logic Help Please

Post by paulsantangelo »

Gorgon:

Do you think a Jtag or FPGA programmer would program a GAL22V10?

I happened to have one in my drawer, I had forgotten about it, needed it to program a few boards that went bad, a few years ago. Did I mention I was absent minded!

-paul
Gorgon
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Re: Logic Help Please

Post by Gorgon »

Hi Paul,
I don't think it is possible, a JTAG programmer is normally just a serial interface between the PC and the serial JTAG chain.

But, if in doubt look to the specification on the device. I think you need an eprom programmer to do this.

TOK ;)
Gorgon the Caretaker - Character in a childrens TV-show from 1968. ;)
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