I need a microcontroller board for control purposes (reading anolog/digital inputs, digital outputs, exact timing,...) Many years ago I was programming a 80C31 unit, so my first approach would be to purchase a couple of 80C31 chips, develop a corresponding board (PCB) with RAM and EPROM, purchase an EPROM programmer, develop a BIOS for this system that allows me to send test programs via a RS232 line from the PC to the unit. That's how I would have done it 20 years ago. Is there any easier solution in the meanwhile? I would love to see an off-the-shelf board with I/O ports (may be 80C31 based, but another controller would do as well) and ideally an ethernet interface (as a replacement for the RS232 interface for programming the unit). But I need an open system, nothing closed with a proprietary windows software to talk with the unit. So if I want ethernet I suppose I need a linux based board so that I don't have to write a TCP stack!? That would be fine, as log as I can write my control code in C and access the I/O ports. Any recommendations? Thanks!
First, forget the 8031 and EPROMs. If you want something 51-compatible, there are plenty of faster alternatives with Flash-ROM, e.g. by Atmel and Maxim. The easiest way to add an Ethernet interface to that is the ENC28J60. A few good IP stacks are available for free (uIP would probably be the best in this case). But you will need a C compiler, so you might just as well start with a modern controller architecture, like something ARM-based. The AT91SAM7X* comes with built-in Ethernet, and you can get free example programs, some with RTOS, for many of the popular boards. If you want Linux, you need a bigger controller, but it doesn't make sense to use Linux just for Ethernet/IP. If that's all too much and you just want a simple drop-in RS232 replacement, take a look at the Lantronix Xport. It will work fine even with the real 80C31.
Perhaps this is something for you: http://www.pollin.de/shop/shop.php?cf=detail.php&pg=Nw==&a=MTQ5OTgxOTk=
If you want to use 8051, then look on the Maxim DS80C400 Evaluation Kit: http://www.maxim-ic.com/quick_view2.cfm/qv_pk/4983 The DS80C400 contain a single cycle 8051-core whith 16MB address range, four data pointers and 16/32-Bit Math Accelerator. The internal Ethernet controller supports Network Boot Over Ethernet Using DHCP and TFTP. Peter
I have been using a STR912 with an ethernet embedded communication, 6 months ago. This microcontroler is interesting because: - ARM9 core - Plenty of RAM: 96K, Until 2Mb of Flash, - Embedded TCP-IP interface - Available in TQFP package (easy for soldering / design) - Supported by : GCC , FreeRTOS (RTOS), UIP (stack TCP) and OpenOCD (al these tools are opensource) - Cheap demo board (Olimex STR912) - Low cost processor But - Not easy to start - Not as documentation as you could find for the very well know Atmel At91, especially for embedded Linux Regards. Damien hoyen