Instructions for
building the RLM interface
------- About the construction.
The interface has 6 inports, 16 outports and DTMF decoder.
The 74HC595 is a SHIFTREGISTER with a built in LATCH and is used for controlling
the out-ports.
The RLM program clocks serial data to the 74HC595 (DATA, CLOCK, LATCH) who put
the data on the parallel ports.
The 74HC151 is a MULTIPLEXER (MUX) and is used for the in-ports.
It has 8 inports and one outport. RLM choose what port to read with a 3-bits
parallel binary code.
The 4050 is a buffer. It only stabilizes the data from the LPT-port.
The transistor is used for muting incoming audiosignals to the DTMF-IC while sound is playing from RLM. This is for eliminating false DTMF-detection.
------- About the PCB.
To get the right scale when you make the PCB, just measure the center of the
pads at the corners.
The long side is 92mm and the short side is 48mm.
Check these things on the pcb before you start soldering.
Use the picture of the pcb for help.
- That's not any copper track is short circuit.
- That's not any pad isn’t frilled.
------- Building.
Start with the 13 jumpers. Use the jumper location picture to check the
placement.
Solder the components. I recommend that you start with the IC:s or IC sockets.
- The resistors are soldered in an upright position.
- I recommend that you use IC sockets for the IC:s for easy changing i
nessesary.
- Place the IC-circuits in the right
direction!
------- Connections
Connecting to the LPT port.
The square pad on the pcb:s lpt-port connector is pin 1
This is a list of how to connect the cable between the PCB and the LPT-port
Dsub.
(PCB-LPT) 1-2, 2-3, 3-4, 4-15, 5-7, 6-8, 7-5, 8-6.
------ Troubleshooting
Ground all inports that's not in use (Very important!).
Test the interface with the "I" menu in the RLM-programs setup. From there, you
can turn ports on and off and check status on the in-ports.
It is important that the power for the interface coming from a well-filtered
source.
A very common problem is that the connection between the interface and the DSUB
LPT-port is wrong. Check several times with help from the list above...
Component list for the RLM-interface
The link in some components iare datasheets in Acrobat reader (PDF) format or a link to a page with more information.
|
Component |
no |
Placement |
ELFA nr. |
Description |
|
1 |
U4 |
73-037-04 |
DTMF decoder, 8pin, serial |
|
|
74HC595 |
2 |
U2, U3 |
73-547-80 |
Shiftregister 8 out |
|
74HC151 |
1 |
U5 |
73-520-24 |
Multiplexer 8 in |
|
4050 |
1 |
U1 |
73-679-23 |
Buffer |
|
1 |
U6 |
73-095-60 |
5v Volt reg. |
|
|
10k |
8 |
R1-6, R10-11 |
60-106-15 |
1/4 Watt resistor |
|
1k |
1 |
R9 |
60-104-90 |
1/4 Watt resistor |
|
100k |
2 |
R7, R8 |
64-367-78 |
Trimpotentiometer |
|
100nF |
2 |
C1, C3 |
64-226-84 |
Plastic capacitor |
|
10uF |
1 |
C2 |
67-003-49 |
Electrolyte capacitor |
|
4.194Mhz |
1 |
Crytal |
74-502-24 |
X-tal for DTMF-ic |
|
BC547 |
1 |
T1 |
71-072-87 |
NPN-Transistor |
|
Other |
|
|
|
|
|
D-sub |
1 |
---- |
44-055-77 |
For printerport 25-pin |
|
SMT 160-30 |
2 |
---- |
73-088-85 |
Smarttemp sensor for in- and outdoor temp |
|
|
|
|
|
|
For further details on components, look at: http://www.elfa.se
(c) 1997-2003 SM2UMH Peter Hansson
www: http://metronic.nu/rlm Version 030830