Talk:WDC 65C816

message: 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)
thread_title:  Title change and merge: "65816 Microprocessor" + "65802 Microprocessor" --> "WDC 65816/65802" 

message: 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)
replies: text: 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)
thread_title:  Source of performance statement wanted 

message: 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)
thread_title:  Advertising removed 

message: 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 . BTW,  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)
replies: text: 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)
thread_title:  SNES 65816 

message: 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)
thread_title:  SuperCPU 

message: Some time in the not-to-distant future I am going to edit this article to be more in line with similar articles for other members of the 6502 family.  Although the 65C816 has the "heart" of a 65C02, it is sufficiently advanced over its eight bit counterpart to warrant a more in-depth treatment, especially on the hardware features that only it has (e.g., the ABORT hardware interrupt).  The present article is mostly a recapitulation of the bullet points from WDC's product page and doesn't give the reader much information beyond the MPU's development history and the systems in which it was/is used.
Bigdumbdinosaur (talk) 04:13, 24 October 2012 (UTC)
thread_title:  Article update 

message: Use of "venerable" to describe the NMOS 6502 is actually quite appropriate once one considers what "venerable" means:
:Definition of venerable
::1a : calling forth respect through age, character, and attainments
::b : impressive by reason of age
Above was copied from the Merriam-Webster on-line dictionary of the English language.
I restored the phrase "venerable MOS Technology 6502 NMOS MPU" because the 6502 indeed meets the requirements of "age, character, and attainments."  Also, that word has been part of the article's intro for nearly 10 years.  I fail to see any good reason to remove it.
:216.152.18.132 (talk) 01:15, 18 June 2022 (UTC)
thread_title:  Venerable 

message: From the intro:
:Despite 24-bit addressing, the 65816 isn't a true 24-bit computer. Programs still operate in 64K chunks since registers are 16-bit.  To access other parts of internal memory a technique similar to bank switching is needed.
The highlighted text is completely false!  Addressing constraints apply only to program execution, not data accesses, and there is no “bank switching.”
Contiguous program code cannot span banks without the use of JML and/or JSL, only because when the program counter (PC) wraps, the program bank (PB) will not increment (which characteristic, in my opinion, was an unnecessary constraint that was apparently the result of Apple’s meddling in the 65C816 design process).  It has nothing to do with register sizes.  A program whose size is greater than 64KB can be executed if JML and/or </code>JSL</code> are used to transfer control between banks.
Data fetches and stores can be bank-aware using 16-bit addressing modes—same as with the 6502/65C02, or bank-agnostic using 24-bit “long” addressing modes.  16-bit addressing is generally one clock cycle faster per memory access, but long addressing can fetch from or store to anywhere in the 16MB space.
I am removing the subject text from the article.
Bigdumbdinosaur (talk) 20:26, 23 May 2023 (UTC)
replies: text: I would have liked to thank you for improving the accuracy of our article -expert attention is always welcome- Bigdumbdinosaur, but I notice you removed much more from the article than what you said you would. The article should, in my opinion, explain what differentiates the 65816 from a true 24-bit processor, i.e. explain the limitations, and ideally, to do so in a reader-accessible manner; i.e. as non-technically as possible. (Precise details only the initiated can appreciate can always be covered later in the article). Also, you removed the part where the processor is contrasted to the MC68000 which all three major suppliers of home computers opted for, including a very valuable historical tidbit (the BYTE interview with the Woz). In order for that piece to fit, the average reader should leave our article with some understanding why that decision was made. Here's hoping you're willing to discuss further improvements to the article.  Regards, CapnZapp (talk) 05:20, 24 May 2023 (UTC)
replies: text:  I'll go ahead and try to reincorporate the cut text into the article as per above. Any expert is welcome to attend the article. CapnZapp (talk) 13:33, 29 May 2023 (UTC)
thread_title:  24-bit addressing 

message: Per WP:LEAD 
In other words, we currently talk about the 65802... but only in the lead. Let's avoid a  tag. CapnZapp (talk) 05:27, 24 May 2023 (UTC)
thread_title:  W65C802