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PIC18 Rapid Prototyping
with off the shelf modular hardware
a la carte by Avalon Engineering

Get a jump on product development with help from Avalon Engineering. Start with a processor board and the PIC18F8722, then add I/O modules as needed. Options include analog input, discrete input, analog output, and discrete output. The processor board includes both RS-232 and RS-485 ports. All you need to add is a 12-24V power supply and some imagination.

Software Developers take note: We give you a head start with more than just hardware. We provide C source code for all of the drivers to access any of the modular I/O with simple function calls.

OEMs and Developers alike will appreciate the Modbus RTU package that makes all of the I/O points accessible via Modbus registers. For the OEM, it's a modular Modbus I/O device ready to run right out of the box. For the software developer, we give you the Modbus source code as a starting point to build your own customized application.

The PIC18F8722 processor board includes an RJ-11 plug for the Microchip ICD2 used for debugging and programming. The BAS-700 I/O bus adds up to 8 I/O modules. The system shown at left includes 4 analog inputs, 4 discrete inputs, and 2 relay outputs. The processor board also includes a 50-pin flat flex connector packed with I/O lines for expansion to a custom interface board.
This PIC18 system includes 8 optically isolated discrete inputs, 8 analog inputs, 8 relay outputs, and 4 analog outputs.
This PIC18 system includes 8 optically isolated discrete inputs, and 16 FET discrete outputs.
Discrete Inputs - 4 and 8 channel optically isolated for AC or DC, or 24-channel TTL level

Discrete Outputs - 2, 4, and 8 channel relay outputs rated to 10A @ 120VAC, or 8-channel FET (1A @ 30VDC sinking)

Analog Inputs - 4 and 8 channel, 0-10VDC, 4-20mA, thermistor, isolation optional.

Analog Outputs - 2 channel, 0-10VDC, 4-20mA.
You can continue to use the off the shelf hardware for product roll-out if you wish. We can also help you streamline the hardware with a custom single board design like the PIC18 based board shown at the right. This one happens to be an industrial pump controller. A 120/240VAC power supply was incorporated onboard along with exactly the needed number of I/O points. The final design was tested to FCC and CE Mark requirements and UL Listed.
This is the semi-custom approach. The custom board contains a mix of sensor signal conditioning and A/D converters, and other miscellaneous I/O such as FET drivers on the PWM outputs. Notice that the BAS-700 I/O bus is continued off the right hand end of the custom board so that custom or off the shelf hardware may be added to accommodate future enhancements.

Call Mark with your PCB Layout, PIC18, and embedded hardware questions at 651-426-8599 ext. 202 or email Mark at mclark@avalon-us.com.

Call Jim with your Modbus Product Development, embedded software, or embedded Internet questions at 651-426-8599 ext. 201 or email Jim at jhogenson@avalon-us.com.