DataMuseum.dk

Presents historical artifacts from the history of:

Commodore CBM-900

This is an automatic "excavation" of a thematic subset of
artifacts from Datamuseum.dk's BitArchive.

See our Wiki for more about Commodore CBM-900

Excavated with: AutoArchaeologist - Free & Open Source Software. 

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⟦762b8c867⟧ TextFile

    Length: 487 (0x1e7)
    Types: TextFile
    Notes: UNIX file
    Names: »ftod.s«

Derivation

└─⟦f27320a65⟧ Bits:30001972 Commodore 900 hard disk image with partial source code
    └─⟦f4b8d8c84⟧ UNIX V7 Filesystem
        └─ ⟦this⟧ »libc/crt/ftod.s«

TextFile

	.globl	dfpack
/ floating point package for segmented z-8001
/ timothy s. murphy  10/84
/ IEEE format
/ double:	63 62		52 51				0
/	      sign  bin exp +1022   fraction (missing hi bit)
/ float:	31 30		23 22				0
/	      sign  bin exp +126    fraction (missing hi bit)
/
	.globl	SS
dfpack:
	subl	rr2, rr2
	testl	rr0
	ret	z

	sub	r5, r5
	rl	r0
	rrc	r5
	sub	r0, $126*256	/ remove bias

	sra	r0		/ c = 0
	sral	r0
	rrc	r2
	sral	r0
	rrc	r2
	sral	r0
	rrc	r2

	add	r0, $1022*16
	or	r0, r5
	ret