Mid Term Report: 11-3-99
Portable Digital Audio CoDec System II (PDACS II)
Group 4 Team Members:
Christopher Medrano
Thomas Pugliese
Scott Robey
Abstract:
The purpose of PDACS is to provide a simple way to record and store audio for later playback. The original PDACS was implemented in the spring of 1999 semester using a Xilinx FPGA. While an FPGA provides for rapid development, a more dedicated processor would have many benefits. Our proposal is to implement PDACS using the Motorola Coldfire MCF5206e embedded processor on a M5206eLITE demo board. Using the MCF5206e processor, we can also simplify the design. Several functions that needed external hardware on the original PDACS can now be done on-chip. We will interface A/D and D/A converters, a LCD, and a keypad. With time permitting we will also add audio compression and a serial interface with GUI. The MCF5206e also has much better performance for both I/O functions and integer calculations.
Introduction:
Individual Achievements:
Scott Robey
Christopher Medrano
Thomas Pugliese
- Hardware issues
- Replaced M-Core board with Coldfire M5206eLITE demo board.
- Got a new M5206eLITE after the first had serial connection problems.
- Located the part number and vendors for SAMTEC interface connectors
- Software
- Installed and obtained licenses for several compilers.
- Tested compilers and set up the one that worked.
- Helped write LCD driver.
- Wrote basic interrupt handler.
I have spent a great deal of time working with different compiler programs on this project and it has proved to be a major setback. Several CD’s were included with the demo board and we also were given a beta copy of Metrowerks CodeWarrior for the MCF5602e. It took a few weeks to get anything to work with the Metrowerks compiler because of its difficult installation and configuration process and a lack of documentation. Once it was working, the only thing we could use it for was to compile S-records, which were then downloaded and executed through a serial connection. The remote debugger crashed too often and practically unusable.
We encountered a problem that took over week to track down. I could not tell if the problem was with hardware or software because the debugger would not run reliably. In the meantime, Chris used the serial connection to get a basic LCD driver running while I installed the other compilers. First I had to wait for demo licenses for the compilers which took time away from the project. Then, I set up each one and went through the setup process. Each one proved difficult or impossible to get working. None of the programs had adequate documentation, which complicated things further. Some required third party compilers or scripting languages. After much trial and error, we got the MULTI Embedded Kit by Green Hills to work and are using it now.
Major or Minor Modifications
The PDACSII project has had some major modifications during the semester. First, we were forced to use the M5206eLITE evaluation board instead of the original M-Core board. This is due to the fact that the M-Core board did not allow access to the chip’s address and data bus. This would have proved to be very difficult when trying to transfer data between the board and the memory module. In addition, obtaining the audio input and output would have been very difficult without the use of parallel transmission. The board had serial interfaces and a few keypad lines but we did not feel that this would be adequate for the design of our project.
Besides the hardware involved, the overall goals of the project have also changed significantly since the beginning of the semester. Time delays involving development software and interface hardware have forced us to scale down the project. The main goal at this point is to interface external devices with the board and provide a reliable development environment with a remote debugger. The devices we plan to interface with the board are:
- D/A and A/D converters
- An LCD display
- Flash memory
- A Keypad
Using these devices we should be able to implement basic functionality of the original PDACS.