The title says it all: I have an Epia N8000E nano-ITX motherboard which has a LPC interface and USB ports, but no standard RS232 serial port. I have a uPD74042B (μPD72042B) IEBus controller that I want to use to connect the Epia to my '08 Prius for the sound system (no aux port in the base model, thank you, and the computer cost me less than the "upgrade" that would have given me such). The biggest problem is that I am not an electrical engineer and so I am unfamiliar with such things as the protocols for communicating via the LPC inerface or what can and cannot communicate with the above controller via its built-in "three-/two-wire serial I/O Transfer starting with LSB" microcomputer interface. There are projects out there for interfacing with the IEBus (called AVCLAN by Toyota) using an ATMega chip (listen with comparator, talk with CAN driver), or a PIC controller. I'm thinking that the overall design would be simpler with an actual IEBus chip; I just need some resources to learn how to interface this chip with a controller capable of interfacing with my computer. So... any ideas/suggestions/help available for me here?
LPC is basically a stripped down version of ISA, usally it's used for flash parts, diagnostic LEDs, and Super IO (SIO) chips. SIO chips are used to provide stuff like parallel ports, serial ports, floppy interface, and keyboard/mouse controllers in a typical PC. I don't know how hard it would be to get an arbitrary SIO or other LPC based system on there, but if you just want RS-232, via can help. Look for the LCP-01 or LPC-02 modules here. That will probally be your best bet to get a PIC or ATMega chip to interface with a minimum of engineering.
Thank you. I'm having trouble finding a source of supply for the LCP-01, but hopefully I'll be able to dig one up. That will simplify matter for me greatly.
USB to serial converter? they cost very little and its going to be much much easier than trying to get the LPC bus to work with something that isnt already written into the bios. Moriquendi
The LPC-01 is Via's so I would expect BIOS support. I didn't realize the part would be so hard to find. I haven't tried a USB to serial adapter in a long time, are they any better than they used to be? I've run into problems in the past with the most frequent being a lack of flow control on the adaptor, but the dev kit or MCU requires flow control. So I've tried to keep something around that has a good old 16550 at 3F8.
