scelbal ported to 8080 cp/m

[aaw...@gmail.com]

Scelbal, if you read Byte magazine in 1970, you saw the ad for a $49 book with the source for a BASIC-like language.  Unfortunately, it was for the 8008.  I was interested in compilers and wanted to read the book.  But not enough to pay $49 for code I couldn't run.

The book, its add-ons (math and strings), and newsletters are available at https://www.willegal.net/scelbi/scelbal.html. But still, close to 50 years later, you still can't run it without an emulator or a super rare 8008 computer. The opcodes are 8008, which I find more annoying than informative.

This project https://github.com/avwohl/scelbal translates the 8008 source to 8080.  Updates done:
 - create names for data locations based on comments and code
 - keep the original ioport code for char/in out
 - provide an easier-to-read 8080 mnemonic copy of the code, staying as close as possible to the original, see src/scelbal8080.asm
 - create a separate version updated to run under cp/m, see src/scelbal.mac
 - create language manual docs/scelbal_language_manual.md