Lexicon Studio - Info / Blog: Recent posts

Work for the past week has been focused on the PCI bus. This is the primary way in and out of the Core32 board. It is also the only way to get the board booted up and running without soldering or changing the board in any way. Since the USB interface is functional, which is all that is required to at least configure and control things, the PCI bus is the next most important thing to tackle.

I downloaded the PCI spec that is relevant, the somewhat old v2.1 spec, and the Motorola PCI application notes for the DSP56K processor. It seems straightforward to provide the signaling that is required. There is a FPGA "core" that is available to take care of the signaling and conversion to 32 bits. It might be necessary to keep that part in the FPGA when high-speed PCI transfers are happening.... read more

A small victory today. Demo code for a stereo USB speaker is working! In between there was a problem with the development tool that prevented connection to the development computer. The dreaded "Failed to get Device ID" error. I seem to have solved it, at least on the board I have, by removing the Ethernet module. It seems there could be some interaction with the voltage that the CPU chip sees and the connection to the PIC24 that is controlling it. Removing extra load on the power supply seems to have fixed it.... read more

I'll try to do these posts regularly, as long as there is something to report.

So yesterday I got the Microchip eval board from Digikey. Bummer that it has the older A3 version chip on it, but I did get some software compiled in the development tool and loaded on the chip. It doesn't do anything useful yet but it means the software build chain is working, so that's something to be happy about.

I took the opportunity to update the MPLabX tool to v2.20, but the new install script had a bug for the version of Linux that I'm using. Finding the solution on the Microchip forums cost me a few hours but I finally got it working.... read more

There are a lot of parts to this project but it can always start small and build from there. These are some of the parts:

• Get the USB 2.0 protocol going from PIC32MZ to a modern OS
• Design the connector board from PIC32MZ to PCI
• Boot the Core32 from PCI with the PIC32MZ
• Write OS level software to send control commands to Core32

I'm going to try to get these all going in at least a small way in a couple of months of spare time effort.... read more

Here we are at day one of a new project. We're going to try to connect Core2 and Core32 PCI boards to USB and take advantage of the well defined and well supported Audio category of USB 2.0 Class2. This should allow any computer running any modern OS to control and stream audio with the Lexicon Studio gear.

We unpacked all the stuff that was in storage, and it's a lot:
- Windows 98 PC with Cubase installed
- Core32 card with the PC90
- three LDI-10T's connected with the LX3
- an LDI-12T... read more