Dale - Computer Science Illuminated 238

Dale - Computer Science Illuminated 238 - wish to output is...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
The Rosetta stone was unearthed by Napoleon’s troops in 1799. The stone contained a proclamation marking the first anniversary of the coronation of Ptolemy V, inscribed in three languages: hieroglyphics, demonic (a cursive version of hieroglyphs), and Greek. Thomas Young, a British physi- cist, and Francois Champollion, a French Egyptologist, were able to decipher the ancient Egyptian languages using the Greek as a guide. Thus, the Rosetta stone provided the key that unlocked the translation of Egyptian hieroglyphics. The Rosetta Stone as a Translation System Program 1 with direct addressing What about the version of program 1 that used direct addressing rather than immediate addressing? We can code it from the same algorithm, but it is more complex. Recall that when using direct addressing we must specify the location in which the character we
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: wish to output is stored. We still have to figure out that address, but we can store the characters there more easily than we did in machine language. We put the *SRII pseudocode operation immediately below the STOP, so that the characters of 26788.2 are stored beginning at location 0010. R6" h#1101,d ; utput 6 R6" h#1100,d ; utput 7 R6" h#110 ,d ; utput 8 R6" h#110 ,d ; utput 8 R6" h#110C,d ; utput . ST P *SRII /6788./ ;St.r7 6788. int. pr.p7r p8ac7s *)ND Here is the screen shot of the assembler listing and the assembled version of the program. Compare the assembled version with the machine language version found on page 204. 211 Copyright The British Museum W...
View Full Document

Ask a homework question - tutors are online