Heathkit ET 3400 Schematic

Page 1

for the

MICROPROCESSOR
TRAINER
Model ET-34OO

595-202 1 -06

\

HEATH COMPANY - BENTON HARBOR, MICHIGAN

Page 2

fillllllllll llllllllllllllllll llllllllllllllllllllll

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HEATH CONRAD ME MY
The lollowlng telephone numbers are direct lines to the departments lbtod:
Kit orders and delivery inlormation ..................... (616) 982-3411

Credit .......... . . . . . (616) 982-3561
Replacement Parts . ,. .. .......... .. (616) 962-3571

Technical Assistance Phone Numbers
8:00 AM. to 12 RM and 1:00 RM. to 4:30 P.M., EST. Weekdays Only

R/C. Audio. and Electronic Organs .................... (616) 962-3310
Amaleur Radio ....................................... (616) 982-3296
Tea Equipment, Weather Instruments and

Home Clocks ....................................... (616) 932-3315
Television ............................................ (616) 9823307

Aircralt. Marine. Security, Scanners. Automotive.
Appliances and General Products ......
Computers ........................

,. (616) 962-3496
.. (616) 982-3309

YOUR HEATHKIT 90-DAY LIMITED WARRANTY

For a period of ninety (90) days alter purchase. Heath Company will replace or repair lrae pl charge any parts that
are deledlve either in materialsor workmanship. You can obtain parts directly lrom Heath Company by writing us at
the address below or by telephoning us at(616l 982-8571. And we'll pay shipping charges to get those parts to you
- anywhere in the world.

We warrant that during lhetirst ninety (90) days alter purchase. ourproducts, when correctly assemhled. calibrated.
adjusted and used in accordance with our primed instructions. will meet published specifications,

ii a detective part or error in design has caused your Heathklt product to mallunoiion during the warranty period
though no lault oi yours. we will urvicc it tree upon prool oi purchase and delivery at your expense to the Heath
laolory. any Haaihkit Electronic Cenmr. or any of our authorized overseas distributors.

You will receive lrea consultation on any problem you might encwnter in the assembly or use at your Heathkit
product. Just drop us a line or give us a call. Sony. we cannot accept collect cells.

Our warranty does not cover and we are not responsible lor damage caused by: incorrect assembly. the use ol
corrosive solder. detective tools. misuse. or tire; or try unauthorized motilioations to or uses ol our produras lor
purposes other than as advertised. Our warranty does not include reimbursement tor inconvenience. low ol use.
customer assembly or set-up time.

This warranty covers only Heathkit products and is not extended to allied equipment or components used in
conjunction with our products. VII Ire not mponolblo tor accidental or conuquentlnl cannon. Some stales
do not allow the exclusion or limitation oi incidental or consequential damages. so the above limitation or exclusion
may not apply to you. This warranty gives you specific legal nails. and you may also have other rigits which vary
lrom state to state

ll you are not satisfied with our service [warranty or otherwise) or with our products. write directly to our Diredcr of
Customer Services. Heath Company. Benton Harbor, Miaiigan 49022, He will make certain your problems receive
immediate. personal attention.

HEATH COMPANV
BENTON HARBOR. Ml. 49022

fiWWWWWWW

The Heath Company reserves the rig to discontinue products and to change specimtions at any lime without
incurring any obligation to incorporate new lectures in products previously sold.

Page 7

_HEATHKIT'

5. Each circuit part in an electronic kit has its own
component number (R2, C4, etc). Use these
numbers when you want to identify the same
part in the various sections of the Manual.
These numbers, which are especially useful if a
part has to be replaced, appear:

- In the Parts List,

- At the beginning of each step where a
component is installed,

- In some illustrations,

- In the Schematic,

- In the section at the rear of the Manual.
7. When you are instructed to cut something to a

particular length, use the scales (rulers) pro-
vided at the bottom of the Manual pages.

SAFETY WARNING: Avoid eye injury when you cut
off excess lead lengths. Hold the leads so they cannot
fly toward your eyes.

Page 5

SOLDERING

Soldering is one of the most important operations you
will perform while assembling your kit. A good sol-
der connection will form an electrical connection be-
tween two parts, such as a component lead and a
circuit board foil. A bad solder connection could pre-
vent an otherwise well-assembled kit from operating

properly.

It is easy to make a good solder connection if you
follow a few simple rules:

1. Use the right type of soldering iron. A 25 to
40-watt pencil soldering iron with a 1/8 or
3/16 chisel or pyramid tip works best.

2. Keep the soldering iron tip clean. Wipe it often
on a wet sponge or cloth; then apply solder to
the tip to give the entire tip a wet look. This
process is called tinning, and it will protect the
tip and enable you to make good connections.
When solder tends to ball" or does not stick to
the tip, the tip needs to be cleaned and retin-
ned.

Page 8

Page 6

PARTS

Resistors will be called out by their resistance value
in 0 (ohms). k0 (kilohms), or M!) (megahms). Certain
types of resistors will have the value printed on the
body, while others will be identified by a color code.
The colors of the bands and the value will be given in
the steps, therefore the following color code is given

for information only. amps} 1 2 3

5-BAND RESISTORS
(1 1 %)

4-BAND RESISTORS

Multiplier

I 0R ""1: ,
1 /4>WATT
El OR m
1 /2~WATI'

Fol-unc-

It Mole Wide

(:10%)
1 ° BA s:
5/0 D 3 Mzflivlier Tolerance
Band 1 Band 2 Band 3 (if used) . . Resistance
lsl Digit 2nd Digit 3rd Digit Multiplier Tolerance
Color Digit Color Diglt Color Digit Color Multiplier Color Tolerance
Black 0 Black 0 Black 0 Black 1 Silver : 10%
Brown 1 Brown 1 Brown 1 Brown 10 Gold 2 5%
Red 2 Pied 2 Red 2 Red 100 Brown : 1%
Orange 3 Orange 3 Orange 3 Orange 1000
Yellow 4 Yellow 4 Yellow 4 Yellow 10,000
Green 5 Green 5 Green 5 Green 100.000
Blue 6 Blue 6 Blue 6 Blue 1,000,000!
Violet 7 Violet 7 Violet 7 Silver 0701
Gray 8 Gray 8 Gray 8 Gold 0 1
White 9 While 9 White 9

i

Capacitors will be called out by their capacitance
value in uF (microfaradsl or pF [picofarads] and type:
ceramic, Mylar, electrolytic, etc. Some capacitors
may have their value printed in the following man-
ner:

First digit of
capacitor's value: 1 r 5 1 it
Second digit 01 V

capacitors value: 5
Multiplier: Multiply the
first 8: second digits by
the proper value from the
Multiplier Chan.

To find the tolerance oi
the capacitor, look up

this letter in the Tolerance
columns.

'DuPont Registered Trademark

MULTIPLIER

FOR THE
NUMBER: BY:

EXAMPLES:

151K = 15 x 10 z 150 pF
759 = 75 xo.1 = 7.5 pF

NOTE: The letter R may be used at times to signify a
decimal point: as in: 2R2 = 2.2 [pF or p.17).

TOLERANCE OF CAPACITOR
10 pF OR
LESS

I :0.1 pF
1!) 20,25 DF
100 :05
1000 :10 pF
10.000 :2.0 pF
100.000

OVER
10 pF

MULTIPLY LETTER

0,01
O.l

B
c
D
F
G
H
J
K
M

Page 15

EJA'II-IIKI'X3

m-

( 1 Install thirty 47D (1 Iyellow«
violet~brown) resistors in the area
shown. After you install each
group of five or six resistors, sol-
der their leads to the foil and cut
offthe excess lead lengths. NOTE:
See "Circuit Board X»RAY
Views in the "Illustration Book-
let" for circuit component num-
bers.

In the next column you will install
diodes. Be sure you install each diode
as follows.

iIPDRIIIIV: Till I!" [tilt of DIODES I
Ii IIIKED III A IIIIEI 0F "IVS.

M

HINDI!) [Ill

CAUTION ALWAYS POSITION THE
BANDED END AS SHOWN ON THE
CIRCUIT BOARD.

j] SOLID BODY
={l:l=

\
BANDED [ND

lfyour diode has a solid body, the band
is clearly defined. If your diode has a
glass body. do not mistake the colored
end inside the diode for the banded
end. Look for a bend painted on the
outside of the glass.

The steps performed in this Pictorial are
in these areas of the circuit board,

Page 13

IDENTIFICATION
DRAWING

, PART
% / NUMBER

{Z}
i:-

3
CO

C"

i,

i

W-

NOTE: Hold the leads with a pair of
long-nosed pliers close to the body of
the diode. Then bend the leads down.

Detail 1-3A

NOTE: As you install the remaining
components on this Pictorial. solder
the leads to the foil and cut off the
excess lead lengths,

D I

I j 010: 1N4149diode(#55-56),

I I R63:470flIyellow-violet»hrown).

I I 16-pin IC socket at 1023.

I
J

I I D5: IN4002 diode I#57»65).

g

I ]R71:4700[yellowvviolet-brown).

I l D6: 1N4002 diode [#57-65].

sss
s

I I lfi'pin IC socket at IC24.

I ] D4: 1N4I102 diode I#57-65).

. ,\ . .
-

I l R79:470flIyellow-violet-brown].

§
\

I ) D3: 1N4002 diode {#57455}.

I ) 16-pin IC socket at IC25.

I ] R87:470nIyellow-violet-brown).

I I 16«pin IC socket at ICZS.

I ) R95t470fiIyelIow-violet-brown).

I J D113A1 diode [#5742]. See De-
tail 1-3A.

I ] 16-pin IC socket at IC27.

I ] DZ: 3A1 diode [#57-42], See De-
tail 1-3A.

I ] R106:47000Iyellowviolet-red].

I ) 16-pin IC socket at IC28.

( JRIM: 470 n Iyellow»violet-
brown].

PICIORIAL 1-3

Page 25

_HEATHKIT'

Page 23

FOIL SIDE
OF CIRCUIT BOARD

IC SOCKET

Detail 1-12D

With the tip of a pencil, push through the three
mounting hole locations in the vinyl strip.

Refer to Detail 1-12C and mount the large con-
nector block on the main circuit board with
three #4 X 5/16" self-tapping screws.

Refer to Detail 1-12D and mount a 3-pin IC
socket at lC29 on the top edge of the circuit
board as shown. Place the edge-mount retainers
over the edge of the circuit board; then rotate
the pins into their holes on the foil side of the
board. Carefully solder the three pins to the foil.

In the same manner. install a 3-pin IC socket at
ICSD.

LEDI: Refer to Detail 1-12E and mount the 3/8
red LED near the rocker switch as shown. Be
sure to match the flat on the LED with the out-
line of the flat on the circuit board. NOTE: Be-
fore you cut off the excess leads. be sure the
bottom edge of the LED is 1/4 above the board.
and that it is not tilted. Solder the leads to the
foil.

CIRCUIT BOARD CHECKOUT

Carefully inspect the foil side of the circuit board for
the following conditions.

[ ) Unsoldered connections.
[ 1 Poor solder connections.

( ) Solder bridges between foil patterns. NOTE: If
you are in doubt about a foil pattern, refer to the
Circuit Board X-Ray View (Illustration Book-
let, Page 18].

( ) Protruding leads which could touch together.

Carefully inspect the component side of the circuit
board for the following conditions.

( ] Integrated circuits for proper type and installa-
tion.

( ) Tantalum capacitors for the correct position of
the positive (+) mark or dot.

[ '1 Diodes for the correct position of the banded
ends.

( ) LEDs for the correct position of the flat sides.

NOTE: There are many unused connections on the
foil side of the main circuit board, some of which will
be used later. As you make further connections to the
circuit board, he Sure to inspect each one carefully to
be sure the foils remain unbridged.

Set the main circuit board aside temporarily.

3/8" RED LED
(12-640)

Detail 1-12E

0 VA /2 3/. 1
#:1153481 5,15 IWal '| IT I' l J |r I l I l I i I | I i I i I i I | I l

0 5 I (cm 2 a A 5 5 1 s a Io 11 12 .3 14 V5 is I7

UNCHES) 2 3 4

Page 70

Page 68

@

OUTCH Routine

OUTCH outputs a character to the display whose ad-
dress is contained at memory location DIGADD
(00F0-00F1]. This routine may be entered at OUTO if
the index register does not need to be saved. The code
for the character to be displayed must be in ac-
cumulator A when the routine is entered. The follow-
ing drawing shows the segment identification and the
corresponding positions in the eight bits of ac-
cumulator A. A logic one in a bit will cause that
segment to light, whereas a logic zero will keep it off.
The hex and corresponding bit codes are shown for
two characters used in the monitor program. The
most significant bit is DP and the least significant bit
is segment g.

Segment codes used by the monitor program are
shown at the end of the monitor listingi

D7 D6 D5 D4 D3 D2 D1 D0

SEGMENT DP 3 b c d e f

HEXC4801001110

LTRcODDOOOllDl

DUTCH ROUTINE

ENTRY: ACCA contains segmenl code. DlGADD con-
tains address ofdesired digit. Entry at DUTO
ii index register is to be saved.

EXIT: DlCADD contains address of next digit to
right.

OUTCH
FECIA

SAVE
(X).

OUTO
F ESC

LOAD)
DIGADD,

i

SAVE
(B).

i

SET UP
(A)

i,

LOAD
(B)
HEX 10,

H-

ROTATE
(A)

i

STORE (A)
AT ADDRESS
IN (X).

i

DECREMENT
(X) AND (B)

YES

STONE (X)
DIGADD

i

RESTORE
(xi AND (a),

db

Page 142

CPU

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,,,,,4 L

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PICTORIAL 9-5

Page 150

CIRCUIT BOARD X-RAY VIEW

NOTE: To find the PART NUMBER of a component
for the purpose of ordering a replacement part:

A Find the circuit component number [R5,
C3, etc.) on the X-Ray Viewl

B. Locate this same number in the Circuit
Component Number" column of the Parts
List."

C. Adjacent to the circuit component number,
you will find the PART NUMBER and DE-

SCRIPTION which must be supplied when
you order a replacement part.

Top foil in red

(Shown from bottom side)

(VSOEQ