Editing H8 Family

{{unreliable sources|date=October 2020}}
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| image = Ic-photo-Hitachi--HD6473238F10--(H8-323-MCU).JPG
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| caption = Hitachi H8/323
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[[File:Plextor PX-W8432Ti - controller board - Hitachi H8S-2357-3929.jpg|thumb|H8S/2357]]
The '''Hitachi H8''' is a large family of [[8-bit]], [[16-bit]] and [[32-bit]] [[microcontroller]]s made by [[Renesas Technology]], originating in the early 1990s within [[Hitachi, Ltd.|Hitachi Semiconductor]]. The original design, the '''H8/300''', was an 8-bit processor that had a 16-bit [[Processor register|registers]] and [[arithmetic logic unit|ALU]] that allowed some 16-bit operations. Two upgraded versions were introduced, the '''H8/300L''' that expanded the instructions to become a full 16-bit machine while being optimized for low cost, and the '''H8/300H''' which further expanded the registers to allow 32-bit operations and was optimized for low-power/high-performance roles. Many variations exist.

The entire line was sold to Renesas in 2003. Renesas continues to sell the designs {{asof|2023|lc=yes}}, but only to existing customers. An administrator on the Renesas user community boards commented in 2011 that there are no plans for further development of H8 based products.<ref>{{cite web |url=https://japan.renesasrulz.com/cafe_rene/f/forum11/1278/h8#pi4368=9 |title=H8はどうなるの|website=Cafe Rene |access-date=24 July 2018}}</ref> H8 was supported in the [[Linux kernel]] starting with version 4.2 but support was removed in version 5.19.<ref>[http://lkml.iu.edu/hypermail/linux/kernel/1506.2/05292.html Git pull request for the H8 port on the LKML archives]</ref>

For higher performance needs, Hitachi introduced its [[SuperH]] family of 32-bit [[RISC]]-like microcontrollers, which have largely replaced the H8.

==Variants==
Subfamilies include the 8/16-bit H8/300 and H8/500, the 16/32-bit H8/300H and H8S and the 32-bit H8SX series, each with dozens of different variants, varying by speed, selection of built-in [[peripheral]]s such as timers, [[interrupt]]s<ref>{{Cite web |url=https://www.renesas.com/us/en/document/mah/h836024-group-h836014-group-hardware-manual?r=1052256 |title=H8/36024Group, H8/36014Group 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series |page=53 |accessdate=2023-12-20}}</ref> and [[serial port]]s, and amounts of [[read-only memory|ROM]], [[flash memory]] and [[random-access memory|RAM]]. Built-in ROM and flash memory tends to range from 16&nbsp;[[kilobyte|KB]] to 1024&nbsp;KB, and RAM from 512&nbsp;[[byte|B]] to 512&nbsp;KB.

The basic architecture of the H8 is patterned after the [[Digital Equipment Corporation|DEC]] [[PDP-11 architecture]], with eight 16-bit [[processor register|register]]s (the H8/300H and H8S have an additional bank of eight 16-bit registers), and a variety of [[addressing mode]]s. Unlike the PDP-11 however, the H8 architecture employs [[big-endian]] [[byte ordering]].

Both H8/300H and H8S have eight 32-bit registers, each of which can be treated as one 32-bit register, two 16-bit registers, or two 8-bit registers, with the H8S having an internal 32-bit configuration.<ref>{{cite web |title=H8S/2116 |publisher=[[Renesas Electronics]] |url=https://www.renesas.com/en-us/products/microcontrollers-microprocessors/h8s/h8s2100/h8s2116.html |access-date=2018-05-12}}</ref> Several companies provide [[compiler]]s for the H8 family, and there is a complete [[GNU Compiler Collection|GCC]] port, including a [[instruction set simulator|simulator]]. There are also various hardware [[in-circuit emulator|emulator]]s available.

The family is continued with the H8SX 32-bit controllers.

==Applications==
[[File:Samsung NC10 - motherboard - Renesas H8S-2110BV-1271.jpg|thumb|Renesas H8S-2110BV]]
H8S may be found in [[digital camera]]s, the [[Cybiko]] handheld computers, some [[ThinkPad]] notebooks,<ref>[http://www.thinkwiki.org/wiki/Renesas_H8S/2161BV Renesas H8S/2161BV on ThinkWiki.org]</ref><ref>[http://www.thinkwiki.org/wiki/Renesas_H8S/2116V Renesas H8S/2116V on ThinkWiki.org]</ref> [[computer printer|printer]] controllers, [[smart card]]s, [[chess computer]]s, music synthesizers such as the [[Yamaha FS1R]],<ref>{{Cite web |url=http://smasher.org/fs1r/inside.html |title=FS1R Inside |access-date=2014-08-19 |archive-date=2014-06-09 |archive-url=https://web.archive.org/web/20140609012756/http://smasher.org/fs1r/inside.html |url-status=dead }}</ref> [[Roland SC-55]] and Roland JV880<ref>{{Citation |last=nukeykt |title=nukeykt/Nuked-SC55 |date=2024-11-24 |url=https://github.com/nukeykt/Nuked-SC55 |access-date=2024-11-24}}</ref> and in various [[automobile|automotive]] subsystems. The [[Lego Mindstorms#RCX|LEGO Mindstorms RCX]], an advanced robot toy/educational tool, uses the H8/300. An H8/3002 was used as a sound processor by [[Namco]] for various games it made in the late 1990s, notably those using its [[Namco System 12|System 12]] architecture and by [[Yamaha Corporation|Yamaha]] for the [[Yamaha XG|DB50XG]] and DB60XG [[daughterboard]]s and the SW60XG [[ISA bus]] [[sound card]].

H8/500 was being also used on a [[Nokia 2110]] phone.

==References==
{{Reflist|2}}

==External links==
* [http://am.renesas.com/products/mpumcu/h8/index.jsp Renesas Electronics]
* [https://elearning.renesas.com/ Online training for Renesas products]
* [http://www.RenesasRulz.com/ A community support forum]

{{Renesas Electronics}}
{{Hitachi}}
{{8bitMCUs}}

[[Category:Renesas microcontrollers]]