Ron Nelson reported that in 1999 he spent 9 months in developing a new 4 Bit chess program which became the foundation for many future Excalibur models as well as its continued use by Excalibur’s successor EB Electronics. The first 4 Bit Model 375 Excalibur LCD Chess was launched in the year 2000. This program can also be found inside many chess computer models sold by other companies such as Radio Shack.
This 4 Bit program seems to be per Nelson’s comments an even further slimmed down version of the original Nelson H8 program, compressed into this much smaller hardware and trimmed with many of the features of the original stronger H8 program removed in order to squeeze a workable chess program into the lesser ram space available on the 4 Bit hardware. This included removal of many of the more sophisticated chess routines used in stronger chess programs such as Nelson’s Attack Bit Map Tables, much smaller opening books, removal of any pondering routines and excess search routines.
Nelson commented on his great interest in developing a capable program suitable for any beginning or hobby chess player and thereby finding larger outlets of distribution for the Excalibur chess products. RadioShack 2-in-1 Chess & Checkers is a very playable and capable chess program ideal for most players was one of the many creations that followed as a result of this nine month period of new program development in 1999.
RadioShack 2-in-1 Chess & Checkers was sold to Radio Shack by Excalibur. Excalibur contracted the manufacturing to Cybertronics (Expert) in the Shenzen Province of China.
The chess program is Ron Nelson’s Version 3.8 24K 4 Bit program which comprised of his 16K 4 Bit chess program plus 8K additional programming. Part of this additional 8K programming was to create a Universal I/O to allow easier adaptation to other chips used in other Excalibur chess computer models.
For reading of Ron Nelson comments go to: Hiarcs Forum