SP0256 Program Counter - Revision history

Mr z: Protected "SP0256 Program Counter" ([edit=autoconfirmed] (indefinite) [move=autoconfirmed] (indefinite))

2010-12-04T09:12:11Z

Protected "SP0256 Program Counter" ([edit=autoconfirmed] (indefinite) [move=autoconfirmed] (indefinite))

Mr z at 22:43, 18 January 2005

2005-01-18T22:43:08Z

Mr z at 22:36, 18 January 2005

2005-01-18T22:36:50Z

Mr z at 22:34, 18 January 2005

2005-01-18T22:34:56Z

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The microsequencer in the SP0256 conceptually maintains a 16-bit Program Counter. The PC points to a byte address, since all branches are to byte boundaries. Internally, the PC may actually be a 19-bit bit-aligned counter.

All serial speech ROMs keep a shadow copy of the PC.

← Older revision		Revision as of 22:43, 18 January 2005
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		+	[[Category:Intellivoice]]
		+
	The microsequencer in the SP0256 conceptually maintains a 19-bit Program Counter. The upper 16 bits of the PC form a byte address. On control transfers (branches and returns), the upper 16 bits of the PC get set to the byte address of the target, and the lower 3 bits initialize to 0.		The microsequencer in the SP0256 conceptually maintains a 19-bit Program Counter. The upper 16 bits of the PC form a byte address. On control transfers (branches and returns), the upper 16 bits of the PC get set to the byte address of the target, and the lower 3 bits initialize to 0.

	All serial speech ROMs keep a shadow copy of the PC as a function of the [[SP0256 Serial Bus Protocol]].		All serial speech ROMs keep a shadow copy of the PC as a function of the [[SP0256 Serial Bus Protocol]].

← Older revision		Revision as of 22:36, 18 January 2005
Line 1:		Line 1:
−	The microsequencer in the SP0256 conceptually maintains a 16-bit Program Counter. The PC ~~points to~~ a byte address, ~~since all branches are~~ to byte ~~boundaries. Internally~~, the ~~PC may actually be a 19-bit bit-aligned counter~~.	+	The microsequencer in the SP0256 conceptually maintains a 19-bit Program Counter. The upper 16 bits of the PC form a byte address. On control transfers (branches and returns), the upper 16 bits of the PC get set to the byte address of the target, and the lower 3 bits initialize to 0.

−	All serial speech ROMs keep a shadow copy of the PC.	+	All serial speech ROMs keep a shadow copy of the PC as a function of the [[SP0256 Serial Bus Protocol]].

← Older revision	Revision as of 09:12, 4 December 2010
(No difference)