RS485 Communication
It has been decided that the Mindstorms brick will communicate with the Tmote with a RS485 communication interface. On the NXT this interface is situated on the 4th RJ11 port.
In these days I’m trying to find out information on the RS485, since I’m going to develop a serial software protocol. As asserted at wednesday’s meeting, and specified by the documentation I’ve found on the web, the interface hardware requires a half-duplex transmission protocol (It seems however that the consecuences of a wrong use of a RS485 interface shouldn’t be so critical).
Looking at the AT91SAM7S256 documentation I discovered how to enable the write process on the interface:
The USART is set in RS485 mode by programming the USART_MODE field in the Mode Register (US_MR) to the value 0×1.
On the header file provided by ATMEL I’ve actually found the memory location to be written. Good thing! Obviously I can’t do any experiment yet…
I’ll use the Bookmarks section of this blog in order to stick any eventually useful website…
Preemptive realtime scheduler?
The NXoS operating system that I’ve started to examinate two weeks ago implements a simple round-robin scheduler. On the NxOS website the authors claim that a preemptive real time scheduler is under development. An investigation is required: I’ve sent them a mail…
Filed under: Objectives, Organization
