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Testing Odd Components

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channelmaniac:
 This thread will be dedicated to testing odd parts or doing uncommon tests on common and uncommon parts!

To kick it off, here's a way to test Triacs:

Remove the device from the circuit, being VERY careful to ensure the circuit is not energized!

Take a digital ohmmeter and test between the different legs on the device: T1, T2, and Gate. Each resistance test will be VERY high, if not infinity, EXCEPT for T1 to Gate.

Gate to T1: 10 to 200 ohms
T1 to Gate: Infinity
T1 to T2: Infinity
T2 to T1: Infinity
T2 to Gate: Infinity
Gate to T2: Infinity

Now, there are some exceptions! Some Triacs will read from 10 to 200 ohms BOTH WAYS between T1 and Gate.

Next, attach one meter lead to T1 and the other to T2. Use a screwdriver blade to short between T2 and Gate. The resistance between T1 and T2 will drop to around 15 to 50 ohms. If it does not, reverse the leads on T1 and T2 then try again. One way will read infinite and the other will read low resistance when T2 and Gate are shorted together.

This method isn't foolproof, but is a good general test to check for a shorted triac.

channelmaniac:
If you have an EPROM programmer from EETools that uses the Max Loader software and it doesn't support testing of a particular 74xx or 4xxx series logic chip, they can be added manually!

The lg.dat file in the c:\program files\EETools directory contains the data for those ICs. It is trivial to add items to that file, provided you structure them properly.

Here are the values that can be entered into each spot:

0 - Logic Low Input
1 - Logic High Input
L - Logic Low Output
H - Logic High Output
Z - High Impedance Output (Chip disconnected from bus)
C - Clocking - Pin transitions from low to high
X - Don't Care.
G - Ground Pin
V - Vcc, or Power Pin (+5v)

An example of this is a 7421/74LS21/etc, which is a Dual 4-input AND Gate and not on the list of ICs for the burner to test. The logic table is as follows:


--- Code: ---Inputs   Output
A B C D    Y
---------------
H H H H    H
L X X X    L
X L X X    L
X X L X    L
X X X L    L

--- End code ---

ALL 4 inputs must be high for the output to be high. Gate 1 uses pins 1, 2, 4, and 5 for input and 6 for the output. Gate 2 uses 9, 10, 12, and 13 for input and 8 for the output. Pin 7 is ground, pin 14 is Vcc (power), and both 3 and 11 are not used. A value of 0 is placed in the location of the unused pins.

The structure of the data file for chip to be defined starts with a dot, the chip number, some spaces, and the # of pins on the chip.


--- Code: ---.7421 14

--- End code ---

So with this in mind, here is the entry for the 7421:


--- Code: ---.7421 14
00000LGL00000V
10000LGL10000V
01000LGL01000V
11000LGL11000V
00010LGL00010V
10010LGL10010V
01010LGL01010V
11010LGL11010V
00001LGL00001V
10001LGL10001V
01001LGL01001V
11001LGL11001V
00011LGL00011V
10011LGL10011V
01011LGL01011V
11011HGH11011V

--- End code ---

This walks through all 16 possible combinations for the 4 inputs. It is possible to do this in as few as 5 lines, which is what the truth table (logic function table) shows, but for a more thorough test, all possible combinations for the inputs should be tested.

This chip definition can be added to the end of the file or in the appropriate ordered place within the file. If it is placed at the end of the file then you must scroll all the way to the end of the file to choose it. The added benefit of defining the IC chip in this file is that it will then be used when clicking "Auto Find" to ID a chip.

Enjoy!

channelmaniac:
For the lg.dat file, it appears that X is for "don't care"...

Using that nomenclature, here is the text to add to the lg.dat file to test an Intel 8216 "4 bit bi-directional bus driver" IC.


--- Code: ---.8216 16
0XL0XL0G0LX0LX0V
0XH1XL0G0LX0LX0V
0XL0XH1G0LX0LX0V
0XL0XL0G1HX0LX0V
0XL0XL0G0LX1HX0V
0XH1XH1G1HX1HX0V
0L0XL0XGX0LX0L1V
0H1XL0XGX0LX0L1V
0L0XH1XGX0LX0L1V
0L0XL0XGX1HX0L1V
0L0XL0XGX0LX1H1V
0H1XH1XGX1HX1H1V
--- End code ---

If you put it at the top of the file, it will be the first chip in the list.

A REALLY cool thing about adding this chip is that once added, the programmer will detect it using the "Auto Detect" function!!!

Enjoy!

channelmaniac:
Here is a 7489, 74289, AM27LS02, and Intel P3101A test:


--- Code: ---.7489 16
0000X0XGX0X0000V
001XZXZGZXZX000V
1000X0XGX0X0000V
101XZXZGZXZX000V
0000X0XGX0X0001V
001XZXZGZXZX001V
1000X0XGX0X0001V
101XZXZGZXZX001V
0000X0XGX0X0010V
001XZXZGZXZX010V
1000X0XGX0X0010V
101XZXZGZXZX010V
0000X0XGX0X0011V
001XZXZGZXZX011V
1000X0XGX0X0011V
101XZXZGZXZX011V
0000X0XGX0X0100V
001XZXZGZXZX100V
1000X0XGX0X0100V
101XZXZGZXZX100V
0000X0XGX0X0101V
001XZXZGZXZX101V
1000X0XGX0X0101V
101XZXZGZXZX101V
0000X0XGX0X0110V
001XZXZGZXZX110V
1000X0XGX0X0110V
101XZXZGZXZX110V
0000X0XGX0X0111V
001XZXZGZXZX111V
1000X0XGX0X0111V
101XZXZGZXZX111V
0001X1XGX1X1000V
001XLXLGLXLX000V
1001X1XGX1X1000V
101XLXLGLXLX000V
0001X1XGX1X1001V
001XLXLGLXLX001V
1001X1XGX1X1001V
101XLXLGLXLX001V
0001X1XGX1X1010V
001XLXLGLXLX010V
1001X1XGX1X1010V
101XLXLGLXLX010V
0001X1XGX1X1011V
001XLXLGLXLX011V
1001X1XGX1X1011V
101XLXLGLXLX011V
0001X1XGX1X1100V
001XLXLGLXLX100V
1001X1XGX1X1100V
101XLXLGLXLX100V
0001X1XGX1X1101V
001XLXLGLXLX101V
1001X1XGX1X1101V
101XLXLGLXLX101V
0001X1XGX1X1110V
001XLXLGLXLX110V
1001X1XGX1X1110V
101XLXLGLXLX110V
0001X1XGX1X1111V
001XLXLGLXLX111V
1001X1XGX1X1111V
101XLXLGLXLX111V
--- End code ---

These chips have open collector outputs so they needed to be set to Z instead of H on outputs for high as there are no resistors tying the outputs high. Or, one could build an adapter with the appropriate resistors to allow for full testing.


This is for a 74189 (tri-state):


--- Code: ---.74189 16
0000X0XGX0X0000V
001XHXHGHXHX000V
1000X0XGX0X0000V
101XHXHGHXHX000V
0000X0XGX0X0001V
001XHXHGHXHX001V
1000X0XGX0X0001V
101XHXHGHXHX001V
0000X0XGX0X0010V
001XHXHGHXHX010V
1000X0XGX0X0010V
101XHXHGHXHX010V
0000X0XGX0X0011V
001XHXHGHXHX011V
1000X0XGX0X0011V
101XHXHGHXHX011V
0000X0XGX0X0100V
001XHXHGHXHX100V
1000X0XGX0X0100V
101XHXHGHXHX100V
0000X0XGX0X0101V
001XHXHGHXHX101V
1000X0XGX0X0101V
101XHXHGHXHX101V
0000X0XGX0X0110V
001XHXHGHXHX110V
1000X0XGX0X0110V
101XHXHGHXHX110V
0000X0XGX0X0111V
001XHXHGHXHX111V
1000X0XGX0X0111V
101XHXHGHXHX111V
0001X1XGX1X1000V
001XLXLGLXLX000V
1001X1XGX1X1000V
101XLXLGLXLX000V
0001X1XGX1X1001V
001XLXLGLXLX001V
1001X1XGX1X1001V
101XLXLGLXLX001V
0001X1XGX1X1010V
001XLXLGLXLX010V
1001X1XGX1X1010V
101XLXLGLXLX010V
0001X1XGX1X1011V
001XLXLGLXLX011V
1001X1XGX1X1011V
101XLXLGLXLX011V
0001X1XGX1X1100V
001XLXLGLXLX100V
1001X1XGX1X1100V
101XLXLGLXLX100V
0001X1XGX1X1101V
001XLXLGLXLX101V
1001X1XGX1X1101V
101XLXLGLXLX101V
0001X1XGX1X1110V
001XLXLGLXLX110V
1001X1XGX1X1110V
101XLXLGLXLX110V
0001X1XGX1X1111V
001XLXLGLXLX111V
1001X1XGX1X1111V
101XLXLGLXLX111V
--- End code ---

And this is for an AMD AM29701 which is identical to the 74189 except for having non-inverting outputs:


--- Code: ---.29701 16
0000X0XGX0X0000V
001XLXLGLXLX000V
1000X0XGX0X0000V
101XLXLGLXLX000V
0000X0XGX0X0001V
001XLXLGLXLX001V
1000X0XGX0X0001V
101XLXLGLXLX001V
0000X0XGX0X0010V
001XLXLGLXLX010V
1000X0XGX0X0010V
101XLXLGLXLX010V
0000X0XGX0X0011V
001XLXLGLXLX011V
1000X0XGX0X0011V
101XLXLGLXLX011V
0000X0XGX0X0100V
001XLXLGLXLX100V
1000X0XGX0X0100V
101XLXLGLXLX100V
0000X0XGX0X0101V
001XLXLGLXLX101V
1000X0XGX0X0101V
101XLXLGLXLX101V
0000X0XGX0X0110V
001XLXLGLXLX110V
1000X0XGX0X0110V
101XLXLGLXLX110V
0000X0XGX0X0111V
001XLXLGLXLX111V
1000X0XGX0X0111V
101XLXLGLXLX111V
0001X1XGX1X1000V
001XHXHGHXHX000V
1001X1XGX1X1000V
101XHXHGHXHX000V
0001X1XGX1X1001V
001XHXHGHXHX001V
1001X1XGX1X1001V
101XHXHGHXHX001V
0001X1XGX1X1010V
001XHXHGHXHX010V
1001X1XGX1X1010V
101XHXHGHXHX010V
0001X1XGX1X1011V
001XHXHGHXHX011V
1001X1XGX1X1011V
101XHXHGHXHX011V
0001X1XGX1X1100V
001XHXHGHXHX100V
1001X1XGX1X1100V
101XHXHGHXHX100V
0001X1XGX1X1101V
001XHXHGHXHX101V
1001X1XGX1X1101V
101XHXHGHXHX101V
0001X1XGX1X1110V
001XHXHGHXHX110V
1001X1XGX1X1110V
101XHXHGHXHX110V
0001X1XGX1X1111V
001XHXHGHXHX111V
1001X1XGX1X1111V
101XHXHGHXHX111V

--- End code ---

channelmaniac:
Here is the code to test the 82S16, a 256 x 1 bipolar RAM with inverted outputs. It also works for the Fairchild 93421 bipolar RAM and the test code is 1024 lines long.

It operates in this fashion:

Write 0 to address 0
Read from address 0
..
Write 0 to address 11111111 (255)
Read from address 11111111 (255)

Then repeat for writing a 1 and reading it back for each address.

It's too big to post as text, so here's an attachment.

Enjoy!

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