 SX Multi Board
Submitted to Parallax by Guenther Daubach
Due to the thoroughness and precise details of this application, we are only offering the complete version as a download (.pdf).
The board’s main features are:
- Size: 2.95 x 2.5 Inches (75*63.5 mm).
- Four-layer PCB with two inner supply layers for enhanced protection against electromagnetic interference.
- All components are non-SMT, i.e. components can be installed without special tools.
- Socket pads for on SX 28 ACT together with a ceramic resonator, and an optional reset circuit.
- The board is divided into three sections, the “main” section, the “RS-232 adapter” section, and the “voltage regulator” section.
- All SX 28 port pins are externally available via a pin-header (depending on certain components installed on the board, some port pins are used for special purposes).
- The “RS-232 adapter”, and the “voltage regulator” section may be cut or broken off when not needed, leaving a “main” section with a minimum size of 2*1.8 Inches (50.5*46 mm). Both, the “RS-232 adapter”, and “voltage regulator” sections, when cut/broken off can be used as stand-alone modules.
- Optional serial I²C EEPROM.
- Optional components for one bitstream continuous calibration ADC channel.
- Separate pin-headers for an external I²C bus, and for TTL-level serial communication, e.g. for Parallax BASIC stamp modules.
- Up to three on-board indicator LEDs.
- Breadboarding area with solder pads for additional components.
- Two 2*2 jumper blocks for I²C bus pull-up resistors, and to configure handshake lines for the TTL serial communications port.
The .pdf will cover the following topics in detail:
“Populating” the SX 28 Multi Board
Reset Circuit
ADC/DAC Support
I²C Support
EEPROM Section
TTLCOMM Port
RS-232 Interface
Status LEDs
Extension Port
Voltage Regulator Section
Adding ISP Support
Selecting the Size of the SX 28 Multi Board
The “Mini Board”
The “RS-232, Externally Powered Board”
The “Non-RS-232 Board with Voltage Regulator”
The “Full-Sized” Board
RS-232 Interface Section
Voltage Regulator section
 Contact Information:
Guenther Daubach
MDA EDV-Beratung GmbH
Im Eulenflug 25
D-51399 Burscheid, Germany
Tel./Fax: +49 2174 – 785 931
email: info@mda-burscheid.de
home: http://www.g-daubach.com
The SX Multi Board is a general-purpose PCB for the SX 28 microcontroller, well suited for various applications for home and commercial use, or for prototyping. My company uses the board for production of a new version of the well-known RS-232/I²C Adapter/Monitor, and for some other customer-specific applications. |