PDQ Board Lite
Microcontroller development board and instrument prototyping platform
for embedded and real-time systems
Overview
The PDQ Board Lite is a low cost single board computer (SBC) and development board that hosts the Freescale HCS12/9S12 MCU and an embedded RTOS. This GNU C programmable instrument controller is ideal for data acquisition and control, PWM drive, I2C sensor interfacing, laboratory automation, scientific instruments, SCADA, instrumentation and automation.
The PDQ Board Lite is an even lower cost version of the PDQ Board with less memory and without some lesser used features (like RS485 and the battery backed calendar clock). It uses the same Freescale HCS12 processor and it is programmed in the same way, using the Mosaic IDE Plus. Its MC9S12A512 processor is operated in single-chip mode, relying on only the processor's internal memory. The PDQ Board Lite provides all the I/O of the processor chip itself, including dual logic level and standard RS-232 serial ports, analog inputs, I2C, dual SPI links, PWM, and timer-controlled digital I/O. The dimensions are the same as those of the PDQ Board, with the same analog and digital I/O headers. It does not include Wildcard headers, and does not support most Wildcards. The board is powered by +5 Volts delivered via one of the IO headers or from a standard micro-USB connector, the same type used on many cell phone chargers.
Programming the PDQ Board Lite using the C language is very similar to programming the standard PDQ Board. The Mosaic IDE+ is a comprehensive GNU C development environment (an alternative to CodeWarrior) that simplifies the coding of your multitasking application. The main restrictions to keep in mind are that RAM is limited to 9 KB, and that software functions associated with missing hardware (Wildcard bus, RS485, real-time clock, etc.) should not be invoked.
Due to RAM limitations, the PDQ Board Lite cannot be natively programmed in Forth, and C coding techniques associated with the onboard Forth system are restricted.
So, to get started programming with the PDQ Board Lite, first read through its specific documentation, in this PDQ Board Lite section of the website. These pages describe the differences between the PDQ Board and the PDQ Board Lite. From there on, refer to the full PDQ Board documentation, keeping in mind the relevant restrictions for the PDQ Board Lite.
See also → Single Board Computers