• Built-in ISP Program Port
• RS232 interface (Max232 converter)
• Direct LCD hookup - holes on PCB match display
• Support for LCD backlight
• I/O pins and to prototyping area
• Tough 62 mil PCB with 1 oz. traces plated
• Parts Kit Now Available for 2313 PCBs
• Assembled/Tested 2313HQ Units Now Available

I'm pleased to introduce the new AVRProject MEGA PCB: It supports the AT90S8535, Mega16, and Mega32 AVR Processors. Testing and evaluation has been complete and the first run of 200 PCBs have been built.

I still have plenty of the 2313LC and HQ PCBs along with a half dozen completed units and parts kits.

The decision to only produce 'LC' versions of the MEGA PCB is twofold and equally important. The first reason is that it's cheaper. In these economic times, money is tight for the hobbyist. The second reason stems from the artwork on the component side of the PCB. If there were annular rings and through-hole plating, a lot of the intricate annotation artwork would get obliterated.

A great deal of design time was worked on the silkscreen artwork. Every pin is labeled so you won't need to jump back and forth between papers and PDF files. As I'm going to be one of the most frequent users, and I've used other manufacturer's PCBs, this was one of the more frustrating points with those other leading brands.

The ADC Input conditioning resistors stem from my constant use of ADCs in testing equipment. I'm frustrated by other manufacturer's simply point all the ADC signals to the nearest IDE header and forget about that function. I chose to make the ADCs the most important part of this PCB.

ADC Noise reduction is one of the primary concerns with using the AT90S8535 and MegaX uProcs. This improvement has been demonstrated in side by side tests of other prototype PCBs having no noise reduction. No government type studies, just simple notice of how the numbers jumped around on the other PCBs.

Internal EEPROM - Sore subject. It took me a whole day to diagnose and fix. Atmel says only location 0 is corrupted.. Hogwash! Every 60 or so power cycles corrupts random EEPROM locations throughout. In an unprotected AVR, it is very, very sad. The only fix is a Dallas DS1233 Reset chip. Few people use the internal EEPROM, but it's important to keep this in mind should the desire arise. There is a place for the optional Reset chip. The DS1233 is not cheap, though it is a hard fix. I've had to store text in the EEPROM since the program was too big on the 90S2313. Those units are still working right after one year of use.

The downloadable BASCOM-AVR compiler will program this PCB for the first 2K of flash ROM. Purchase of the full blown version will allow programming up to 32K for the Mega-32 on this PCB.