Talk:WDC 65816/65802
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[edit] Title change and merge: "65816 Microprocessor" + "65802 Microprocessor" --> "WDC 65816/65802"
Why the name change? In short: because <company name> <processor name>, where <company name> belongs to the originating company, is the de facto standard for microprocessor articles in WKP. Note that this also applies to processors which are/have been second-sourced (i.e., manufactured by one or more companies other than the originating one).
Rationale for the article merge: It seemed natural, as the 65802 is a straighforwardly "feature-reduced" version of the 65816. The 65816 is listed first in the title, as that processor is the main variant of the two. --Wernher 14:54, 16 July 2005 (UTC)
[edit] Source of performance statement wanted
I removed the following from the article: "It worked at 1,5 mips." Could the contributor or others please give a source of performance figures for the 65816/802 processors? It would be an OK addition to the article. --Wernher 14:12, 17 October 2005 (UTC)
- The performance of the 65C816 measured in MIPS will be basically the same as in 6502, just the 65C816 can work with much higher clock speeds. here (the snapshot on the right) is an example benchmark for a 14 MHz 65C816, and it averages at 3,1 MIPS. The result could be better, but memory writes, which are a part of the test, are slow on that machine. 82.210.159.30 12:23, 4 June 2006 (UTC)
[edit] Advertising removed
The recently added material that looked like direct advertising from WDC's website was removed by me. The feature list, which I wikified, gives all the information needed, in a more neutral manner. --Wernher 15:12, 27 February 2006 (UTC)
[edit] SNES 65816
It would be nice to know how exactly the SNES's "customised" 65816 differs. According to SA-1 chip, it's a (Ricoh?) 5a22. It seems that there might not be much difference from a software point of view, though [1]. BTW, {{MOS CPU}} has an entry for "Ricoh 5a22"... If someone can confirm that this is really the SNES CPU, we can have that redirect here. --StuartBrady 23:51, 7 March 2006 (UTC)
- The SNES CPU is a Ricoh 5A22, which is based on the 65c816; if there are any differences in the core, I don't know about it. However, it has a number of additional features in the package: DMA logic, joypad reading circuitry, interrupt generation circuitry, multiplication and division hardware, an additional address bus, and a variable clock divisor based on the memory region accessed. The SA-1 is also based on the 65c816 with additional features: DMA logic, interrupt generation circuitry, internal RAM, additional arithmetic circuits, bitmap format conversion circuitry, a barrel shifter for variable data access of 1-16 bits, access collision avoidance, memory mapping circuitry, and an integrated version of Nintendo's CIC lockout chip. Anomie 16:21, 21 October 2007 (UTC)
[edit] SuperCPU
According to List of home computers by category, there was a (third party?) external CMD SuperCPU accelerator for the Commodore 64 and C128. Would that be worth mentioning and if so, where? --StuartBrady 00:06, 14 March 2006 (UTC)
[edit] Successor to 6502 or 6510?
It seems to me that this 65816/65802 builds upon, not the 6502 but its successor the 6510 (which has more capability). - Theaveng 10:48, 21 October 2007 (UTC)
Not so! The 6510 did not have "more capability," whatever that means. It (the 6510) had the exact same instruction set as the 6502, complete with the same limitations and bugs, e.g., the malfunctioning JMP(xxFF) problem. Also, the 6510, like the 6502, was an NMOS part and was only available in two clock speeds.
The 65816/65802 have always been CMOS parts, are available in much higher clock speeds than the 6510, and like the 65C02, work correctly. JMP(xxFF) behaves as it should, a BRK executed at the same time an IRQ occurs is honored, etc.
Also, the CMOS lineage actually existed before the 6510. Western Design Center and Rockwell were both shipping 65C02s in 1981. I know, because I used one to modify a CBM 8000 machine.
