Intel MCS-48: Difference between revisions
imported>Stepho-wrs Restored piped links. Short acronyms have a tendency to be replaced with redirects to completely different articles in completely different fields. |
imported>ToaneeM Undid revision 1322683358 by RastaKins (talk) Removed another unproposed/undiscussed and unbeneficial code lump. Reinstated original article before change. Have repeatedly asked for discussion (and have started one) but Rastkins keeps edit warring. (Do not revoke this edit. Do not edit war. Again, please first propose and discuss any changes on Talk page and reach agreement.) |
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{| class="infobox" style="font-size:88%;width:21em;" | {| class="infobox" style="font-size:88%;width:21em;" | ||
|- | |- | ||
|+ Intel 8048 registers | |+ Intel 8048 registers<ref name="MCS-48 UM"/> | ||
|- | |- | ||
| | | | ||
| Line 32: | Line 32: | ||
| style="text-align:center;" colspan="10"| PC | | style="text-align:center;" colspan="10"| PC | ||
| style="background:white; color:black;"| '''P'''rogram '''C'''ounter | | style="background:white; color:black;"| '''P'''rogram '''C'''ounter | ||
|- | |||
|colspan="17" | '''Timer/Counter''' | |||
|- style="background:silver;color:black" | |||
| style="text-align:center; background:white" colspan="2" | | |||
| style="text-align:center;" colspan="8"| T | |||
| style="width:auto; background:white; color:black;"| '''T'''imer | |||
|- | |- | ||
|colspan="17" | '''Program Status Word''' | |colspan="17" | '''Program Status Word''' | ||
| Line 38: | Line 44: | ||
| style="text-align:center;"| [[Carry flag|CY]] | | style="text-align:center;"| [[Carry flag|CY]] | ||
| style="text-align:center;"| [[Half-carry flag|AC]] | | style="text-align:center;"| [[Half-carry flag|AC]] | ||
| style="text-align:center;"| | | style="text-align:center;"| F0 | ||
| style="text-align:center;"| BS | | style="text-align:center;"| BS | ||
| style="text-align:center;"| 1 | | style="text-align:center;"| 1 | ||
| style="text-align:center;" colspan="3"| Stack | | style="text-align:center;" colspan="3"| [[Stack register|Stack]] | ||
|- | |||
|colspan="17" | '''Flags''' | |||
|- style="background:silver;color:black" | |||
| style="text-align:center; background:white" colspan="6" | | |||
| colspan="2"; style="text-align:center;"| DBF | |||
| style="text-align:center;"| F1 | |||
| style="text-align:center;"| [[Interrupt flag|I]] | |||
|- | |- | ||
|colspan="20" | Note: All other programmer-visible registers and stack are allocated in RAM. | |colspan="20" | Note: All other programmer-visible registers and stack are allocated in RAM. | ||
| Line 49: | Line 62: | ||
The '''MCS-48''' [[microcontroller]] series, [[Intel]]'s first microcontroller, was originally released in 1976. Its first members were '''8048''', '''8035''' and '''8748'''. The 8048<ref name= computerHistory >{{cite conference |first1=David |last1=Laws |first2=Henry |last2=Blume Jr. |first3=John |last3=Ekiss |first4=Yung |last4=Feng |first5=Barbara |last5=Kline |first6=Howard |last6=Raphael |first7=David |last7=Stamm |url=http://archive.computerhistory.org/resources/access/text/2013/05/102658328-05-01-acc.pdf |date=2008-07-30 |archive-url=https://web.archive.org/web/20141227131405/http://archive.computerhistory.org/resources/access/text/2013/05/102658328-05-01-acc.pdf |archive-date=2014-12-27 |title=Oral History Panel on the Development and Promotion of the Intel 8048 Microcontroller}}</ref> is arguably the most prominent member of the family. Initially, this family was produced using [[NMOS logic|NMOS]] (n-type [[metal–oxide–semiconductor]]) technology. In the early 1980s, it became available in [[CMOS]] technology. It was manufactured into the 1990s to support older designs that still used it. | The '''MCS-48''' [[microcontroller]] series, [[Intel]]'s first microcontroller, was originally released in 1976. Its first members were '''8048''', '''8035''' and '''8748'''. The 8048<ref name= computerHistory >{{cite conference |first1=David |last1=Laws |first2=Henry |last2=Blume Jr. |first3=John |last3=Ekiss |first4=Yung |last4=Feng |first5=Barbara |last5=Kline |first6=Howard |last6=Raphael |first7=David |last7=Stamm |url=http://archive.computerhistory.org/resources/access/text/2013/05/102658328-05-01-acc.pdf |date=2008-07-30 |archive-url=https://web.archive.org/web/20141227131405/http://archive.computerhistory.org/resources/access/text/2013/05/102658328-05-01-acc.pdf |archive-date=2014-12-27 |title=Oral History Panel on the Development and Promotion of the Intel 8048 Microcontroller}}</ref> is arguably the most prominent member of the family. Initially, this family was produced using [[NMOS logic|NMOS]] (n-type [[metal–oxide–semiconductor]]) technology. In the early 1980s, it became available in [[CMOS]] technology. It was manufactured into the 1990s to support older designs that still used it. | ||
The MCS-48 series has a [[modified Harvard architecture]], with internal or external program [[ | The MCS-48 series has a [[modified Harvard architecture]], with internal or external program [[ROM]] and 64 to 256 bytes of internal (on-chip) [[RAM]]. The [[I/O]] is mapped into its own [[address space]], separate from programs and data. | ||
Though the MCS-48 series was eventually replaced by the very successful [[ | Though the MCS-48 series was eventually replaced by the very successful [[MCS-51]] series, it remained quite popular even by the year 2000 due to its low cost, wide availability, memory-efficient one-byte instruction set, and mature development tools. Because of this, it is used in high-volume, cost-sensitive consumer electronics devices such as TV remotes, computer keyboards, and toys. | ||
== Variants == | == Variants == | ||
The '''8049''' has 2 KB of masked [[ | The '''8049''' has 2 KB of masked [[ROM]] (the 8748 and 8749 had [[EPROM]]) that can be replaced with a 4 KB external ROM, as well as 128 [[byte]]s of [[RAM]] and 27 [[I/O]] ports.{{sfn|Intel Corporation|1978}} The microcontroller's [[Electronic oscillator|oscillator]] block divides the clock input frequency by three and then further divides the result into five machine states. Using the 11 [[MHz]] maximum crystal frequency will produce 0.73 [[Instructions per second#Millions of instructions per second (MIPS)|MIPS]] of single-cycle [[instruction set architecture|instruction]]s. Some 70% of instructions are single byte and single cycle ones, but 30% need two cycles or two bytes, so its typical performance would be closer to 0.5 MIPS. | ||
{| class="wikitable" | {| class="wikitable" | ||
|+Microcontroller | |+Microcontroller<ref name="MCS-48 UM"/> | ||
! Device !! | ! Device !! Program memory !! Data memory !! Remarks | ||
|- | |- | ||
| 8020 || 1K × 8 ROM || 64 × 8 RAM || subset of 8048, 20 pins, only 13 I/O lines | | 8020 || 1K × 8 ROM || 64 × 8 RAM || subset of 8048, 20 pins, only 13 I/O lines | ||
| Line 93: | Line 106: | ||
{| class="wikitable" | {| class="wikitable" | ||
|+Universal Peripheral Interface | |+Universal Peripheral Interface | ||
! Device !! | ! Device !! Program memory !! Data memory !! Remarks | ||
|- | |- | ||
| 8041 || 1K × 8 ROM || 64 × 8 RAM || Universal Peripheral Interface (UPI) | | 8041 || 1K × 8 ROM || 64 × 8 RAM || Universal Peripheral Interface (UPI) | ||
| Line 113: | Line 126: | ||
== Uses == | == Uses == | ||
The MCS-48 series was commonly used in computer and terminal keyboards, converting key presses into protocols that can be understood by digital circuits. This also allows the possibility of serial communication, reducing the | The MCS-48 series was commonly used in computer and terminal keyboards, converting key presses into protocols that can be understood by digital circuits. This also allows the possibility of serial communication, reducing the number of conductors needed in cables on external keyboards. Microprocessors had been used in keyboards since at least 1972, simplifying earlier discrete designs. The 8048 has been used in this application since its introduction in 1978.{{cn|date=March 2023}} | ||
The Tandy/Radio Shack [[TRS-80 Model II]], released in 1979, used the 8021 in its keyboard.<ref>{{cite book |title=TRS-80 Model II Technical Reference Manual |publisher=Radio Shack |page=135}}</ref> The 8021 processor scans the key matrix, converts switch closures to an 8-bit code and then transmits that code serially to the keyboard interface on the main system. It will also accept commands to turn indicator LEDs on or off. The 8021 was also used in the keyboards for the TRS-80 Model 12, 12B, 16, 16B and the Tandy 6000/6000HD.<ref>{{cite book |title=Tandy 6000/6000HD Service Manual |date=1985 |publisher=Tandy/Radio Shack |page=213}}</ref> | The Tandy/Radio Shack [[TRS-80 Model II]], released in 1979, used the 8021 in its keyboard.<ref>{{cite book |title=TRS-80 Model II Technical Reference Manual |publisher=Radio Shack |page=135}}</ref> The 8021 processor scans the key matrix, converts switch closures to an 8-bit code and then transmits that code serially to the keyboard interface on the main system. It will also accept commands to turn indicator LEDs on or off. The 8021 was also used in the keyboards for the TRS-80 Model 12, 12B, 16, 16B and the Tandy 6000/6000HD.<ref>{{cite book |title=Tandy 6000/6000HD Service Manual |date=1985 |publisher=Tandy/Radio Shack |page=213}}</ref> | ||
The original [[IBM PC keyboard]] used an 8048 as its internal [[microcontroller]].<ref>{{Citation |title=Technical Reference: Personal Computer |series=Personal Computer Hardware Reference Library |chapter=Section 4: Keyboard |publisher=[[IBM]] |date=April 1984 |edition=Revised}}</ref> The [[ | The original [[IBM PC keyboard]] and the keyboard for its precursor the [[IBM System/23 Datamaster]] used an 8048 as its internal [[microcontroller]].<ref>{{Citation |title=Technical Reference: Personal Computer |series=Personal Computer Hardware Reference Library |chapter=Section 4: Keyboard |publisher=[[IBM]] |date=April 1984 |edition=Revised}}</ref> The [[PC AT]] replaced the PC's [[Intel 8255]] peripheral interface chip at I/O port addresses {{mono|[[hexadecimal|0x]]60–63}} with an 8042 accessible through port addresses {{mono|0x60}} and {{mono|0x64}}.<ref>{{Citation |title=Technical Reference: Personal Computer AT |series=Personal Computer Hardware Reference Library |chapter=Section 1: System Board |publisher=IBM |date=September 1985}}</ref> As well as managing the keyboard interface, the 8042 controlled the [[A20 line]] gating function for the AT's [[Intel 80286]] CPU and could be commanded by software to reset the 80286 (unlike the [[80386]] and later processors, the 80286 had no way of switching from [[protected mode]] back to [[real mode]] except by being reset). Later PC compatibles integrate the 8042's functions into their [[super I/O]] devices. | ||
The 8048 was used in the [[Magnavox Odyssey²]] [[video game console]], the [[Korg Trident]] series,<ref>{{Cite web|title=Korg Trident Service Manual|url=http://www.synthfool.com/docs/Korg/Korg_Trident_Service_manual/ |page=4 |publisher=Korg |via=Synthfool |access-date=10 February 2018}}</ref> and the [[Korg Poly-61]],<ref>{{cite web|title=Korg Poly-61 Service Manual|url=http://fa.utfs.org/diy/korgpoly61/Korg_Poly-61_ServiceManual.pdf|access-date=2013-03-07|archive-date=2010-06-02|archive-url=https://web.archive.org/web/20100602041214/http://fa.utfs.org/diy/korgpoly61/Korg_Poly-61_ServiceManual.pdf|url-status=dead}}</ref> [[Roland Jupiter-4]] and [[Roland ProMars]]<ref name="SOS11-04">{{cite web|title=The History Of Roland, Part 1: 1930–1978|url=http://www.soundonsound.com/sos/nov04/articles/roland.htm|work=The History Of Roland|publisher=Sound On Sound Magazine|access-date=29 November 2010|author=Gordon Reid|date=November 2004}}</ref> [[analog synthesizer]]s. The [[Sinclair QL]] used the closely related Intel 8049 to manage its keyboard, joystick ports, RS-232 inputs and audio. The ROM-less 8035 variant was used in [[Nintendo]]'s arcade game ''[[Donkey Kong (arcade game)|Donkey Kong]]'' to generate the background music. | The 8048 was used in the [[Magnavox Odyssey²]] [[video game console]], the [[Korg Trident]] series,<ref>{{Cite web|title=Korg Trident Service Manual|url=http://www.synthfool.com/docs/Korg/Korg_Trident_Service_manual/ |page=4 |publisher=Korg |via=Synthfool |access-date=10 February 2018}}</ref> and the [[Korg Poly-61]],<ref>{{cite web|title=Korg Poly-61 Service Manual|url=http://fa.utfs.org/diy/korgpoly61/Korg_Poly-61_ServiceManual.pdf|access-date=2013-03-07|archive-date=2010-06-02|archive-url=https://web.archive.org/web/20100602041214/http://fa.utfs.org/diy/korgpoly61/Korg_Poly-61_ServiceManual.pdf|url-status=dead}}</ref> [[Roland Jupiter-4]] and [[Roland ProMars]]<ref name="SOS11-04">{{cite web|title=The History Of Roland, Part 1: 1930–1978|url=http://www.soundonsound.com/sos/nov04/articles/roland.htm|work=The History Of Roland|publisher=Sound On Sound Magazine|access-date=29 November 2010|author=Gordon Reid|date=November 2004}}</ref> [[analog synthesizer]]s. The [[Sinclair QL]] used the closely related Intel 8049 to manage its keyboard, joystick ports, RS-232 inputs and audio. The ROM-less 8035 variant was used in [[Nintendo]]'s arcade game ''[[Donkey Kong (arcade game)|Donkey Kong]]'' to generate the background music and some of the game's sound effects. | ||
==Instruction set== | |||
All MCS-48 instructions are one or two bytes long with 70% of the instructions being one byte. The MCS-48 can address 4096 bytes of program memory, 256 bytes of RAM, and eight port I/O addresses. Most arithmetic and logical operations use the accumulator as a parameter and destination. Eight memory locations are mapped as registers so they can be addressed by a 3-bit field embedded in many instructions. Two of those registers can be used as memory pointers. Conditional branches can only access the current 256-byte page. JMP and CALL can directly access 2048 locations. To access the entire 4096 byte program space, a clunky select memory bank instruction must be used. The RET instruction can, however, return anywhere in the address space. Interrupts are well supported with alternate registers for quick context switches and the ability to restore the state of the flags with the RETR instruction. All instructions execute in one or two machine cycles. Each machine cycle takes 15 external clocks.<ref name="MCS-48 UM">{{cite book |title=MCS-48 Family of Single Chip Microcomputers User's Manual |date=September 1980 |publisher=Intel |edition=AFN·01300A-1 |url=http://www.bitsavers.org/components/intel/8048/1980_MCS-48_Users_Manual.pdf |access-date=15 November 2025}}</ref> | |||
{|class="wikitable mw-collapsible" style="text-align:center" | |||
!colspan=8| Opcode ||rowspan=2| Operand ||rowspan=2| Mnemonic || rowspan=2| Cycles ||rowspan=2| Description | |||
|- | |||
! 7 || 6 || 5 || 4 || 3 || 2 || 1 || 0 | |||
|- | |||
| 0 || 0 || 0 || 0 || 0 || 0 || 0 || 0 || — ||align=left| NOP || 1 ||align=left| No operation | |||
|- | |||
| 0 || 0 || 0 || 0 || 0 || 0 || 1 || 0 || — ||align=left| OUTL BUS,A || 2 ||align=left| Bus latch ← A | |||
|- | |||
|colspan=4|ALUI|| 0 || 0 || 1 || 1 || data ||align=left| ADD ADDC MOV ORL ANL XRL || 2 ||align=left| A ← A ALU # | |||
|- | |||
| colspan=3|addhi|| 0 || 0 || 1 || 0 || 0 || addlo ||align=left| JMP add || 2 ||align=left| PC ← DBF:addhi:addlo | |||
|- | |||
| 0 || 0 || 0 || I || 0 || 1 || 0 || 1 || — ||align=left| EN/DIS I || 1 ||align=left| I ← 0 (EN) or I ← 1 (DIS) | |||
|- | |||
| 0 || 0 || 0 || 0 || 0 || 1 || 1 || 1 || — ||align=left| DEC A || 1 ||align=left| A ← A - 1 | |||
|- | |||
| 0 || 0 || 0 || 0 || 1 || 0 || 0 || 0 || — ||align=left| INS A,BUS || 2 ||align=left| A ← bus | |||
|- | |||
| 0 || 0 || 0 || 0 || 1 || 0 ||colspan=2|PP|| — ||align=left| IN A,Pp || 2 ||align=left| A ← Port(p) (Ports 1-2) | |||
|- | |||
| 0 || 0 || 0 || 0 || 1 ||colspan=3|PP|| — ||align=left| MOVD A,Pp || 2 ||align=left| A<sub>0-3</sub> ← 8243 Port(p); A<sub>4-7</sub> ← 0 (Ports 4-7) | |||
|- | |||
|colspan=4|ALU|| 0 || 0 || 0 || R || — ||align=left| INC XCH ORL ANL ADD ADDC<br>MOVaA XRL MOVAa || 1 ||align=left| dest ← dest ALU @Rr (@R0, @R1 only; no DEC) | |||
|- | |||
|colspan=4|ALU|| 1 ||colspan=3|RRR|| — ||align=left| INC XCH ORL ANL ADD ADDC<br>MOVaA DEC XRL MOVAa || 1 ||align=left| dest ← dest ALU Rr | |||
|- | |||
|colspan=3|BIT|| 1 || 0 || 0 || 1 || 0 || addr ||align=left| JBb addr || 2 ||align=left| If A ∧ (1 << b) then PC<sub>0-7</sub> ← addr | |||
|- | |||
| colspan=3|addhi|| 1 || 0 || 1 || 0 || 0 || addlo ||align=left| CALL add || 2 ||align=left| (SP) ← PSW<sub>4-7</sub>:PC; SP ← SP + 1; PC ← DBF:addhi:addlo | |||
|- | |||
| 0 || 0 || 0 || 1 || 0 || 1 || 1 || 0 || addr ||align=left| JTF addr || 2 ||align=left| If TF = 1 then PC<sub>0-7</sub> ← addr (timer flag set) | |||
|- | |||
| 0 || 0 || 0 || 1 || 0 || 1 || 1 || 1 || — ||align=left| INC A || 1 ||align=left| A ← A + 1 | |||
|- | |||
| 0 || 0 || 1 || T || 0 || 1 || 0 || 1 || — ||align=left| EN/DIS TCNTI || 1 ||align=left| TCNTI ← 0 (EN) or TCNTI ← 1 (DIS) (timer/counter interrupt) | |||
|- | |||
| 0 || 0 || 1 || F || 0 || 1 || 1 || 0 || addr ||align=left| JNT0 JT0 addr || 2 ||align=left| If F = T0 then PC<sub>0-7</sub> ← addr (test input 0) | |||
|- | |||
| 0 || 0 || 1 || 0 || 0 || 1 || 1 || 1 || — ||align=left| CLR A || 1 ||align=left| A ← 0 | |||
|- | |||
| 0 || 0 || 1 || 1 || 0 || 1 || 1 || 1 || — ||align=left| CPL A || 1 ||align=left| A ← ¬A | |||
|- | |||
| 0 || 0 || 1 || 1 || 1 || 0 ||colspan=2|PP|| — ||align=left| OUTL Pp,A || 2 ||align=left| Port(p) ← A (Ports 1-2) | |||
|- | |||
| 0 || 0 || 1 || 1 || 1 ||colspan=3|PP|| — ||align=left| MOVD Pp,A || 2 ||align=left| 8243 Port(p) ← A<sub>0-3</sub> (Ports 4-7) | |||
|- | |||
| 0 || 1 || 0 || 0 || 0 || 0 || 1 || 0 || — ||align=left| MOV A,T || 1 ||align=left| A ← T (Move timer to A) | |||
|- | |||
| 0 || 1 || 0 || T || 0 || 1 || 0 || 1 || — ||align=left| STRT CNT/T || 1 ||align=left| If T = 0 start count else start timer | |||
|- | |||
|| 0 || 1 || 0 || F || 0 || 1 || 1 || 0 || addr ||align=left| JNT1 JT1 addr || 2 ||align=left| If F = T1 then PC<sub>0-7</sub> ← addr (test input 1) | |||
|- | |||
| 0 || 1 || 0 || 0 || 0 || 1 || 1 || 1 || — ||align=left| SWAP A || 1 ||align=left| A<sub>0-3</sub> ↔ A<sub>4-7</sub> | |||
|- | |||
| 0 || 1 || 0 || 1 || 0 || 1 || 1 || 1 || — ||align=left| DA A || 1 ||align=left| If A<sub>0-4</sub> > 9 OR AC = 1 then A ← A + 6; | |||
then if A<sub>4-7</sub> > 9 OR C = 1 then A ← A + 0x60 | |||
|- | |||
| 0 || 1 || 1 || 0 || 0 || 0 || 1 || 0 || — ||align=left| MOV T,A || 1 ||align=left| T ← A (Move A to timer) | |||
|- | |||
| 0 || 1 || 1 || 0 || 0 || 1 || 0 || 1 || — ||align=left| STOP TCNT || 1 ||align=left| Stop timer and count | |||
|- | |||
| 0 || 1 || 1 || 0 || 0 || 1 || 1 || 1 || — ||align=left| RRC A || 1 ||align=left| C ← A<sub>0</sub>; A<sub>0-6</sub> ← A<sub>1-7</sub>; A<sub>7</sub> ← C | |||
|- | |||
| 0 || 1 || 1 || 1 || 0 || 1 || 0 || 1 || — ||align=left| ENT0 CLK || 1 ||align=left| Set T0 as a clock output | |||
|- | |||
| 0 || 1 || 1 || 1 || 0 || 1 || 1 || 0 || addr ||align=left| JF1 addr || 2 ||align=left| If F1 = 1 then PC<sub>0-7</sub> ← addr | |||
|- | |||
| 0 || 1 || 1 || 1 || 0 || 1 || 1 || 1 || — ||align=left| RR A || 1 ||align=left| A<sub>0-6</sub> ← A<sub>1-7</sub>; A<sub>7</sub> ← A<sub>0</sub> | |||
|- | |||
| 1 || 0 || 0 || 0 || 0 || 0 || 1 || 1 || — ||align=left| RET || 2 ||align=left| SP ← SP - 1; PC ← (SP) | |||
|- | |||
| 1 || 0 || N || 0|| 0 || 1 || 0 || 1 || — ||align=left| CLR Fn || 1 ||align=left| Fn ← 0 | |||
|- | |||
| 1 || 0 || 0 || 0 || 0 || 1 || 1 || 0 || addr ||align=left| JNI addr || 2 ||align=left| If I input = 0 then PC<sub>0-7</sub> ← addr (test interrupt input low) | |||
|- | |||
| 1 || 0 || 0 || 0 || 1 || 0 || 0 || 0 || data ||align=left| ORL BUS,# || 2 ||align=left| A ← bus ∨ # | |||
|- | |||
| 1 || 0 || 0 || 0 || 1 || 0 ||colspan=2|PP|| data ||align=left| ORL Pp,# || 2 ||align=left| A ← Port(p) ∨ # (Ports 1-2) | |||
|- | |||
| 1 || 0 || 0 || 0 || 1 ||colspan=3|PP|| — ||align=left| ORLD Pp,A || 2 ||align=left| 8243 Port(p) ← 8243 Port(p) ∨ A<sub>0-3</sub> (Ports 4-7) | |||
|- | |||
| 1 || 0 || 0 || 1 || 0 || 0 || 1 || 1 || — ||align=left| RETR || 2 ||align=left| SP ← SP - 1; PC ← (SP); PSW<sub>4-7</sub> ← (SP) | |||
|- | |||
| 1 || 0 || N || 1|| 0 || 1 || 0 || 1 || — ||align=left| CPL Fn || 1 ||align=left| Fn ← ¬Fn | |||
|- | |||
| 1 || 0 || 0 || 1|| 0 || 1 || 1 || 1 || — ||align=left| CLR C || 1 ||align=left| C ← 0 | |||
|- | |||
| 1 || 0 || 0 || 1 || 1 || 0 || 0 || 0 || data ||align=left| ANL BUS,# || 2 ||align=left| A ← bus ∧ # | |||
|- | |||
| 1 || 0 || 0 || 1 || 1 || 0 ||colspan=2|PP|| data ||align=left| ANL Pp,# || 2 ||align=left| A ← Port(p) ∧ # (Ports 1-2) | |||
|- | |||
| 1 || 0 || 0 || 1 || 1 ||colspan=3|PP|| — ||align=left| ANLD Pp,A || 2 ||align=left| 8243 Port(p) ← 8243 Port(p) ∧ A<sub>0-3</sub> (Ports 4-7) | |||
|- | |||
| 1 || 0 || 1 || 0 || 0 || 0 || 1 || 1 || — ||align=left| MOVP A,@A || 2 ||align=left| A ← ROM(PC<sub>8-11</sub>:A) (read program memory) | |||
|- | |||
| 1 || 0 || 1 || 0|| 0 || 1 || 1 || 1 || — ||align=left| CPL C || 1 ||align=left| C ← ¬C | |||
|- | |||
| 1 || 0 || 1 || 1 || 0 || 0 || 1 || 1 || — ||align=left| JMPP @A || 2 ||align=left| PC<sub>0-7</sub> ← A (indirect JMP) | |||
|- | |||
| 1 || 0 || 1 || 1 || 0 || 1 || 1 || 0 || addr ||align=left| JF0 addr || 2 ||align=left| If F0 = 1 then PC<sub>0-7</sub> ← addr | |||
|- | |||
| 1 || 1 || 0 || N || 0 || 1 || 0 || 1 || — ||align=left| SEL RBn || 1 ||align=left| BS ← n (select register bank) | |||
|- | |||
| 1 || 1 || 0 || 0 || 0 || 1 || 1 || 0 || addr ||align=left| JZ addr || 2 ||align=left| If A = 0 then PC<sub>0-7</sub> ← addr | |||
|- | |||
| 1 || 1 || 0 || 0 || 0 || 1 || 1 || 1 || — ||align=left| MOV A,PSW || 1 ||align=left| A ← PSW | |||
|- | |||
| 1 || 1 || 0 || 1 || 0 || 1 || 1 || 1 || — ||align=left| MOV PSW,A || 1 ||align=left| PSW ← A | |||
|- | |||
| 1 || 1 || 1 || 0 || 0 || 0 || 1 || 1 || — ||align=left| MOVP3 A,@A || 2 ||align=left| A ← ROM(0011:A) (read page 3 program memory) | |||
|- | |||
| 1 || 1 || 1 || N || 0 || 1 || 0 || 1 || — ||align=left| SEL MBn || 1 ||align=left| DBF ← n (select memory bank: PC<sub>11</sub>) | |||
|- | |||
| 1 || 1 || 1 || F || 0 || 1 || 1 || 0 || addr ||align=left| JNC JC addr || 2 ||align=left| If F = C then PC<sub>0-7</sub> ← addr | |||
|- | |||
| 1 || 1 || 1 || 0 || 0 || 1 || 1 || 1 || — ||align=left| RL A || 1 ||align=left| A<sub>1-7</sub> ← A<sub>0-6</sub>; A<sub>0</sub> ← A<sub>7</sub> | |||
|- | |||
| 1 || 1 || 1 || 0 || 1 ||colspan=3|RRR || addr ||align=left| DJNZ Rr,addr || 2 ||align=left| Rr ← Rr - 1; If Rr ≠ 0 then PC<sub>0-7</sub> ← addr | |||
|- | |||
| 1 || 1 || 1 || 1 || 0 || 1 || 1 || 1 || — ||align=left| RLC A || 1 ||align=left| C ← A<sub>7</sub>; A<sub>1-7</sub> ← A<sub>0-6</sub>; A<sub>0</sub> ← C | |||
|- | |||
! 7 || 6 || 5 || 4 || 3 || 2 || 1 || 0 || Operand || Mnemonic || Cycles || Description | |||
|- | |||
!colspan=12| | |||
|- | |||
!colspan=4|RRR or R|| 3 || 2 || 1 || 0 ||colspan=2 | ALU||colspan=2| ALUI #immed | |||
|- | |||
|colspan=4| R0 @R0 || 0 || 0 || 0 || 0 || style="text-align: left;" colspan=2 | || style="text-align: left;" colspan=2|ADD A,# (A ← A + #) | |||
|- | |||
|colspan=4| R1 @R1 || 0 || 0 || 0 || 1|| style="text-align: left;" colspan=2 |INC arg (arg ← arg + 1) || style="text-align: left;" colspan=2|ADDC A,# (A ← A + # + C) | |||
|- | |||
|colspan=4| R2 || 0 || 0 || 1 || 0||style="text-align: left;" colspan=2 |XCH A,arg (A ↔ arg) || style="text-align: left;" colspan=2|MOV R,# (R ← #) | |||
|- | |||
|colspan=4| R3 || 0 || 0 || 1 || 1|| style="text-align: left;" colspan=2 | | |||
|- | |||
|colspan=4| R4 || 0 || 1 || 0 || 0|| style="text-align: left;" colspan=2 |ORL A,arg (A ← A ∨ arg) || style="text-align: left;" colspan=2|ORL A,# (A ← A ∨ #) | |||
|- | |||
|colspan=4| R5 || 0 || 1 || 0 || 1|| style="text-align: left;" colspan=2 |ANL A,arg (A ← A ∧ arg) || style="text-align: left;" colspan=2|ANL A,# (A ← A ∧ #) | |||
|- | |||
|- | |||
|colspan=4| R6 || 0 || 1 || 1 || 0|| style="text-align: left;" colspan=2 |ADD A,arg (A ← A + arg) || style="text-align: left;" colspan=2| | |||
|- | |||
|colspan=4| R7 || 0 || 1 || 1 || 1|| style="text-align: left;" colspan=2 |ADDC A,arg (A ← A + arg + C)|| style="text-align: left;" colspan=2| | |||
|- | |||
|colspan=4| || 1 || 0 || 1 || 0||style="text-align: left;" colspan=2 |MOV arg,A (arg ← A) || style="text-align: left;" colspan=2| | |||
|- | |||
|colspan=4| || 1 || 1 || 0 || 0|| style="text-align: left;" colspan=2 |DEC arg (arg ← arg - 1) || style="text-align: left;" colspan=2| | |||
|- | |||
|colspan=4| || 1 || 1 || 0 || 1|| style="text-align: left;" colspan=2 |XRL A,arg (A ← A ⊻ arg) || style="text-align: left;" colspan=2| XRL A,# (A ← A ⊻ #) | |||
|- | |||
|colspan=4| || 1 || 1 || 1 || 1|| style="text-align: left;" colspan=2 |MOV A,arg (A ← arg) | |||
|- | |||
!colspan=4|RRR or R|| 3 || 2 || 1 || 0 ||colspan=2 | ALU||colspan=2|ALUI #immed | |||
|} | |||
== Derived microcontrollers == | == Derived microcontrollers == | ||
Philips Semiconductors (now [[ | Philips Semiconductors (now [[NXP]]) owned a license to produce this series and developed their MAB8400-family based on this architecture. These were the first microcontrollers with an integrated [[I²C]]-interface and were used in the first [[Philips]] ([[Magnavox]] in the US) [[CD player|Compact Disc players]] (e.g. the CD-100).<ref>[http://arquivo.pt/wayback/20160515111736/http://www.datasheetarchive.com/dl/Datasheets-110/DSAP005622.pdf Datasheet (pdf)] Philips MAB8400-Family</ref> | ||
<gallery mode="packed" heights="80px" caption="Intel MCS-48 [[second source]]s"> | <gallery mode="packed" heights="80px" caption="Intel MCS-48 [[second source]]s"> | ||
Latest revision as of 15:53, 17 November 2025
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The MCS-48 microcontroller series, Intel's first microcontroller, was originally released in 1976. Its first members were 8048, 8035 and 8748. The 8048[2] is arguably the most prominent member of the family. Initially, this family was produced using NMOS (n-type metal–oxide–semiconductor) technology. In the early 1980s, it became available in CMOS technology. It was manufactured into the 1990s to support older designs that still used it.
The MCS-48 series has a modified Harvard architecture, with internal or external program ROM and 64 to 256 bytes of internal (on-chip) RAM. The I/O is mapped into its own address space, separate from programs and data.
Though the MCS-48 series was eventually replaced by the very successful MCS-51 series, it remained quite popular even by the year 2000 due to its low cost, wide availability, memory-efficient one-byte instruction set, and mature development tools. Because of this, it is used in high-volume, cost-sensitive consumer electronics devices such as TV remotes, computer keyboards, and toys.
Variants
The 8049 has 2 KB of masked ROM (the 8748 and 8749 had EPROM) that can be replaced with a 4 KB external ROM, as well as 128 bytes of RAM and 27 I/O ports.Template:Sfn The microcontroller's oscillator block divides the clock input frequency by three and then further divides the result into five machine states. Using the 11 MHz maximum crystal frequency will produce 0.73 MIPS of single-cycle instructions. Some 70% of instructions are single byte and single cycle ones, but 30% need two cycles or two bytes, so its typical performance would be closer to 0.5 MIPS.
| Device | Program memory | Data memory | Remarks |
|---|---|---|---|
| 8020 | 1K × 8 ROM | 64 × 8 RAM | subset of 8048, 20 pins, only 13 I/O lines |
| 8021 | 1K × 8 ROM | 64 × 8 RAM | subset of 8048, 28 pins, 21 I/O lines |
| 8022 | 2K × 8 ROM | 64 × 8 RAM | subset of 8048, A/D-converter |
| 8035 | none | 64 × 8 RAM | |
| 8038 | none | 64 × 8 RAM | |
| 8039 | none | 128 × 8 RAM | |
| 8040 | none | 256 × 8 RAM | |
| 8048 | 1K × 8 ROM | 64 × 8 RAM | 27× I/O ports |
| 8049 | 2K × 8 ROM | 128 × 8 RAM | 27× I/O ports |
| 8050 | 4K x 8 ROM | 256 × 8 RAM | |
| 8648 | 1K × 8 OTP EPROM | 64 × 8 RAM | Factory OTP EPROM |
| 8748 | 1K × 8 EPROM[3] | 64 × 8 RAM[3] | 4K program memory expandable,[3] 2× 8-bit timers, 27× I/O ports |
| 8749 | 2K × 8 EPROM | 128 × 8 RAM | 2× 8-bit timers, 27× I/O ports |
| 87P50 | ext. ROM socket | 256 × 8 RAM | Has piggy-back socket for 2758/2716/2732 EPROM |
| Device | Program memory | Data memory | Remarks |
|---|---|---|---|
| 8041 | 1K × 8 ROM | 64 × 8 RAM | Universal Peripheral Interface (UPI) |
| 8041AH | 1K × 8 ROM | 128 × 8 RAM | UPI |
| 8741A | 1K × 8 EPROM | 64 × 8 RAM | UPI, EPROM version of 8041 |
| 8741AH | 1K × 8 OTP EPROM | 128 × 8 RAM | UPI, OTP EPROM version of 8041AH |
| 8042AH | 2K × 8 ROM | 256 × 8 RAM | UPI |
| 8242 | 2K × 8 ROM | 256 × 8 RAM | UPI, preprogrammed with keyboard controller firmware[4] |
| 8742 | 2K × 8 EPROM | 128 × 8 RAM | UPI, EPROM version |
| 8742AH | 2K × 8 OTP EPROM | 256 × 8 RAM | UPI, OTP EPROM version of 8042AH |
Uses
The MCS-48 series was commonly used in computer and terminal keyboards, converting key presses into protocols that can be understood by digital circuits. This also allows the possibility of serial communication, reducing the number of conductors needed in cables on external keyboards. Microprocessors had been used in keyboards since at least 1972, simplifying earlier discrete designs. The 8048 has been used in this application since its introduction in 1978.Script error: No such module "Unsubst".
The Tandy/Radio Shack TRS-80 Model II, released in 1979, used the 8021 in its keyboard.[5] The 8021 processor scans the key matrix, converts switch closures to an 8-bit code and then transmits that code serially to the keyboard interface on the main system. It will also accept commands to turn indicator LEDs on or off. The 8021 was also used in the keyboards for the TRS-80 Model 12, 12B, 16, 16B and the Tandy 6000/6000HD.[6]
The original IBM PC keyboard and the keyboard for its precursor the IBM System/23 Datamaster used an 8048 as its internal microcontroller.[7] The PC AT replaced the PC's Intel 8255 peripheral interface chip at I/O port addresses Template:Mono with an 8042 accessible through port addresses Template:Mono and Template:Mono.[8] As well as managing the keyboard interface, the 8042 controlled the A20 line gating function for the AT's Intel 80286 CPU and could be commanded by software to reset the 80286 (unlike the 80386 and later processors, the 80286 had no way of switching from protected mode back to real mode except by being reset). Later PC compatibles integrate the 8042's functions into their super I/O devices.
The 8048 was used in the Magnavox Odyssey² video game console, the Korg Trident series,[9] and the Korg Poly-61,[10] Roland Jupiter-4 and Roland ProMars[11] analog synthesizers. The Sinclair QL used the closely related Intel 8049 to manage its keyboard, joystick ports, RS-232 inputs and audio. The ROM-less 8035 variant was used in Nintendo's arcade game Donkey Kong to generate the background music and some of the game's sound effects.
Instruction set
All MCS-48 instructions are one or two bytes long with 70% of the instructions being one byte. The MCS-48 can address 4096 bytes of program memory, 256 bytes of RAM, and eight port I/O addresses. Most arithmetic and logical operations use the accumulator as a parameter and destination. Eight memory locations are mapped as registers so they can be addressed by a 3-bit field embedded in many instructions. Two of those registers can be used as memory pointers. Conditional branches can only access the current 256-byte page. JMP and CALL can directly access 2048 locations. To access the entire 4096 byte program space, a clunky select memory bank instruction must be used. The RET instruction can, however, return anywhere in the address space. Interrupts are well supported with alternate registers for quick context switches and the ability to restore the state of the flags with the RETR instruction. All instructions execute in one or two machine cycles. Each machine cycle takes 15 external clocks.[1]
| Opcode | Operand | Mnemonic | Cycles | Description | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | ||||
| 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | — | NOP | 1 | No operation |
| 0 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | — | OUTL BUS,A | 2 | Bus latch ← A |
| ALUI | 0 | 0 | 1 | 1 | data | ADD ADDC MOV ORL ANL XRL | 2 | A ← A ALU # | |||
| addhi | 0 | 0 | 1 | 0 | 0 | addlo | JMP add | 2 | PC ← DBF:addhi:addlo | ||
| 0 | 0 | 0 | I | 0 | 1 | 0 | 1 | — | EN/DIS I | 1 | I ← 0 (EN) or I ← 1 (DIS) |
| 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | — | DEC A | 1 | A ← A - 1 |
| 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | — | INS A,BUS | 2 | A ← bus |
| 0 | 0 | 0 | 0 | 1 | 0 | PP | — | IN A,Pp | 2 | A ← Port(p) (Ports 1-2) | |
| 0 | 0 | 0 | 0 | 1 | PP | — | MOVD A,Pp | 2 | A0-3 ← 8243 Port(p); A4-7 ← 0 (Ports 4-7) | ||
| ALU | 0 | 0 | 0 | R | — | INC XCH ORL ANL ADD ADDC MOVaA XRL MOVAa |
1 | dest ← dest ALU @Rr (@R0, @R1 only; no DEC) | |||
| ALU | 1 | RRR | — | INC XCH ORL ANL ADD ADDC MOVaA DEC XRL MOVAa |
1 | dest ← dest ALU Rr | |||||
| BIT | 1 | 0 | 0 | 1 | 0 | addr | JBb addr | 2 | If A ∧ (1 << b) then PC0-7 ← addr | ||
| addhi | 1 | 0 | 1 | 0 | 0 | addlo | CALL add | 2 | (SP) ← PSW4-7:PC; SP ← SP + 1; PC ← DBF:addhi:addlo | ||
| 0 | 0 | 0 | 1 | 0 | 1 | 1 | 0 | addr | JTF addr | 2 | If TF = 1 then PC0-7 ← addr (timer flag set) |
| 0 | 0 | 0 | 1 | 0 | 1 | 1 | 1 | — | INC A | 1 | A ← A + 1 |
| 0 | 0 | 1 | T | 0 | 1 | 0 | 1 | — | EN/DIS TCNTI | 1 | TCNTI ← 0 (EN) or TCNTI ← 1 (DIS) (timer/counter interrupt) |
| 0 | 0 | 1 | F | 0 | 1 | 1 | 0 | addr | JNT0 JT0 addr | 2 | If F = T0 then PC0-7 ← addr (test input 0) |
| 0 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | — | CLR A | 1 | A ← 0 |
| 0 | 0 | 1 | 1 | 0 | 1 | 1 | 1 | — | CPL A | 1 | A ← ¬A |
| 0 | 0 | 1 | 1 | 1 | 0 | PP | — | OUTL Pp,A | 2 | Port(p) ← A (Ports 1-2) | |
| 0 | 0 | 1 | 1 | 1 | PP | — | MOVD Pp,A | 2 | 8243 Port(p) ← A0-3 (Ports 4-7) | ||
| 0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | — | MOV A,T | 1 | A ← T (Move timer to A) |
| 0 | 1 | 0 | T | 0 | 1 | 0 | 1 | — | STRT CNT/T | 1 | If T = 0 start count else start timer |
| 0 | 1 | 0 | F | 0 | 1 | 1 | 0 | addr | JNT1 JT1 addr | 2 | If F = T1 then PC0-7 ← addr (test input 1) |
| 0 | 1 | 0 | 0 | 0 | 1 | 1 | 1 | — | SWAP A | 1 | A0-3 ↔ A4-7 |
| 0 | 1 | 0 | 1 | 0 | 1 | 1 | 1 | — | DA A | 1 | If A0-4 > 9 OR AC = 1 then A ← A + 6;
then if A4-7 > 9 OR C = 1 then A ← A + 0x60 |
| 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | — | MOV T,A | 1 | T ← A (Move A to timer) |
| 0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | — | STOP TCNT | 1 | Stop timer and count |
| 0 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | — | RRC A | 1 | C ← A0; A0-6 ← A1-7; A7 ← C |
| 0 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | — | ENT0 CLK | 1 | Set T0 as a clock output |
| 0 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | addr | JF1 addr | 2 | If F1 = 1 then PC0-7 ← addr |
| 0 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | — | RR A | 1 | A0-6 ← A1-7; A7 ← A0 |
| 1 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | — | RET | 2 | SP ← SP - 1; PC ← (SP) |
| 1 | 0 | N | 0 | 0 | 1 | 0 | 1 | — | CLR Fn | 1 | Fn ← 0 |
| 1 | 0 | 0 | 0 | 0 | 1 | 1 | 0 | addr | JNI addr | 2 | If I input = 0 then PC0-7 ← addr (test interrupt input low) |
| 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | data | ORL BUS,# | 2 | A ← bus ∨ # |
| 1 | 0 | 0 | 0 | 1 | 0 | PP | data | ORL Pp,# | 2 | A ← Port(p) ∨ # (Ports 1-2) | |
| 1 | 0 | 0 | 0 | 1 | PP | — | ORLD Pp,A | 2 | 8243 Port(p) ← 8243 Port(p) ∨ A0-3 (Ports 4-7) | ||
| 1 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | — | RETR | 2 | SP ← SP - 1; PC ← (SP); PSW4-7 ← (SP) |
| 1 | 0 | N | 1 | 0 | 1 | 0 | 1 | — | CPL Fn | 1 | Fn ← ¬Fn |
| 1 | 0 | 0 | 1 | 0 | 1 | 1 | 1 | — | CLR C | 1 | C ← 0 |
| 1 | 0 | 0 | 1 | 1 | 0 | 0 | 0 | data | ANL BUS,# | 2 | A ← bus ∧ # |
| 1 | 0 | 0 | 1 | 1 | 0 | PP | data | ANL Pp,# | 2 | A ← Port(p) ∧ # (Ports 1-2) | |
| 1 | 0 | 0 | 1 | 1 | PP | — | ANLD Pp,A | 2 | 8243 Port(p) ← 8243 Port(p) ∧ A0-3 (Ports 4-7) | ||
| 1 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | — | MOVP A,@A | 2 | A ← ROM(PC8-11:A) (read program memory) |
| 1 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | — | CPL C | 1 | C ← ¬C |
| 1 | 0 | 1 | 1 | 0 | 0 | 1 | 1 | — | JMPP @A | 2 | PC0-7 ← A (indirect JMP) |
| 1 | 0 | 1 | 1 | 0 | 1 | 1 | 0 | addr | JF0 addr | 2 | If F0 = 1 then PC0-7 ← addr |
| 1 | 1 | 0 | N | 0 | 1 | 0 | 1 | — | SEL RBn | 1 | BS ← n (select register bank) |
| 1 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | addr | JZ addr | 2 | If A = 0 then PC0-7 ← addr |
| 1 | 1 | 0 | 0 | 0 | 1 | 1 | 1 | — | MOV A,PSW | 1 | A ← PSW |
| 1 | 1 | 0 | 1 | 0 | 1 | 1 | 1 | — | MOV PSW,A | 1 | PSW ← A |
| 1 | 1 | 1 | 0 | 0 | 0 | 1 | 1 | — | MOVP3 A,@A | 2 | A ← ROM(0011:A) (read page 3 program memory) |
| 1 | 1 | 1 | N | 0 | 1 | 0 | 1 | — | SEL MBn | 1 | DBF ← n (select memory bank: PC11) |
| 1 | 1 | 1 | F | 0 | 1 | 1 | 0 | addr | JNC JC addr | 2 | If F = C then PC0-7 ← addr |
| 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | — | RL A | 1 | A1-7 ← A0-6; A0 ← A7 |
| 1 | 1 | 1 | 0 | 1 | RRR | addr | DJNZ Rr,addr | 2 | Rr ← Rr - 1; If Rr ≠ 0 then PC0-7 ← addr | ||
| 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | — | RLC A | 1 | C ← A7; A1-7 ← A0-6; A0 ← C |
| 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | Operand | Mnemonic | Cycles | Description |
| RRR or R | 3 | 2 | 1 | 0 | ALU | ALUI #immed | |||||
| R0 @R0 | 0 | 0 | 0 | 0 | ADD A,# (A ← A + #) | ||||||
| R1 @R1 | 0 | 0 | 0 | 1 | INC arg (arg ← arg + 1) | ADDC A,# (A ← A + # + C) | |||||
| R2 | 0 | 0 | 1 | 0 | XCH A,arg (A ↔ arg) | MOV R,# (R ← #) | |||||
| R3 | 0 | 0 | 1 | 1 | |||||||
| R4 | 0 | 1 | 0 | 0 | ORL A,arg (A ← A ∨ arg) | ORL A,# (A ← A ∨ #) | |||||
| R5 | 0 | 1 | 0 | 1 | ANL A,arg (A ← A ∧ arg) | ANL A,# (A ← A ∧ #) | |||||
| R6 | 0 | 1 | 1 | 0 | ADD A,arg (A ← A + arg) | ||||||
| R7 | 0 | 1 | 1 | 1 | ADDC A,arg (A ← A + arg + C) | ||||||
| 1 | 0 | 1 | 0 | MOV arg,A (arg ← A) | |||||||
| 1 | 1 | 0 | 0 | DEC arg (arg ← arg - 1) | |||||||
| 1 | 1 | 0 | 1 | XRL A,arg (A ← A ⊻ arg) | XRL A,# (A ← A ⊻ #) | ||||||
| 1 | 1 | 1 | 1 | MOV A,arg (A ← arg) | |||||||
| RRR or R | 3 | 2 | 1 | 0 | ALU | ALUI #immed | |||||
Derived microcontrollers
Philips Semiconductors (now NXP) owned a license to produce this series and developed their MAB8400-family based on this architecture. These were the first microcontrollers with an integrated I²C-interface and were used in the first Philips (Magnavox in the US) Compact Disc players (e.g. the CD-100).[12]
- Intel MCS-48 second sources
-
Mitsubishi Electric M5M80C39P-6
-
Fujitsu MBL8742H
-
Kvazar Kiev KM1816VE48 (Soviet Union – 8748 clone)
-
National Semiconductor NS87PC48D (piggyback variant)
-
Signetics SCN8048A
-
Philips MAF 8049H
See also
References
Bibliography
- MCS-48
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
- UPI-41
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
- Script error: No such module "citation/CS1".
External links
- MCS-48 family architecture
- Template:Webarchive
- Computer History Museum, Intel 8048 Microcontroller Oral History Panel
- Microcontroller NEC 8741 (image of the Silicon-Chip)
Script error: No such module "Navbox". Template:8bitMCUs
- ↑ a b c Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ a b c Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Datasheet (pdf) Philips MAB8400-Family