This is a Tibbit module — part of the Tibbo Project System that allows you to build your own custom embedded device with only the components you need. Start with a Tibbo Project PCB, add Tibbits like this one, then place the built design into a Tibbo Project Box to complete your product.
Tibbit #08: Wiegand and clock/data reader port plus one open collector output.
The Tibbo Project PCBs have the unique ability to process input from card readers with clock/data or Wiegand interface. This is achieved through the ser object running in the clock/data or Wiegand mode. This Tibbit implements the necessary hardware.
In order to be able to process card reader output, this Tibbit has to be connected to the RX and CTS lines of the CPU's UART (see [SER]).
When connecting a clock/data reader, wire the clock line to IO1, and the data line to IO2. Set the CONTROL line to LOW — this selects the clock/data mode for the Tibbit's hardware.
When connecting a Wiegand reader, wire the W0 line to IO1; W1 line to IO2. Set the CONTROL line to HIGH to select the Wiegand mode.
In both cases, the IO3 line must be connected to the external power source. Most card readers with clock/data and Wiegand interfaces have open-collector outputs. Such outputs require pull-up resistors on the receiving end. On this Tibbit, the role of pull-up resistors is played by opto-LEDs and resistors connected in series.
The exact voltage of the power source depends on the reader. Very often it is the supply voltage for the reader itself (typically, +12V). In this case, just split the reader power line and connect the same power to IO3. Some readers require 12V power and pull-up resistors to 5V. This means IO3 will need to receive +5V.
This Tibbit also has a standalone open-collector output controlled through LINE D. Set LINE D LOW to open the transistor. When left unconnected, the line defaults to HIGH (hence, the transistor is closed).
Combine this Tibbit with a terminal block C Tibbit #20 (nine terminal blocks) or #21 (four terminal blocks). Note however that #21 doesn't provide the ground line which is required between the reader and your system, so you would need to "steal" the ground from somewhere else.
Check out Tibbit #11 (four open-collector outputs) if you are looking to emulate clock/data or Wiegand reader output (i.e. if you want to turn your device into a reader that provides data output).
There are four LEDs. Red LEDs are connected to the CONTROL and OC lines. Green LEDs are connected to W0&1 and W1 lines. All LEDs are buffered (with logic gates) and light up for the LOW state of their control lines.
- Form: M1S
- Power: 5V; consumes 20mA
- Special lines: [SER]
- Mates with: #19, #20, #21 (limited use)
- Similar to: #11
M1S Tibbit Modules Overview M1S Tibbits are single-width modules occupying one standard M socket on a Tibbo Project PCB (i.e. TPP2 or TPP3). Their footprint is roughly 7 × 14 "squares" (one "square" is 2.54 × 2.54 mm). The M1S modules are 12.5mm high.
M1 modules have two rows of 6 pins:
Pins 8-11 are control lines A-D. They provide the interface to programmable modules or other microcontrollers. On Tibbo Project PCBs, these pins are connected to the main processor.
Pins 2-5 are I/O lines facing the outside world. On Tibbo Project PCBs, they go to C Tibbits.
Pins 6 and 12 are the GROUND and +5V power pins. Most Tibbit Modules consume (take) 5V power. There are also power supply Tibbits that generate 5V power from a variety of sources. Those output 5V through pin 12.
Pins 1 and 7 are for the additional +15V and -15V voltages. These are optional and only needed by few Tibbits. A special power supply Tibbit (#12) generates ±15V from the main 5V power.