Common PIAs include the Motorola MC6820 and MC6821, and the MOS Technology MCS6520, all of which are functionally identical but have slightly different electrical characteristics. The PIA is most commonly packaged in a 40 pin DIP package.
The PIA is designed for glueless connection to the Motorola 6800 style bus, and provides 20 I/O lines, which are organised into two 8-bit bidirectional ports (or 16 general-purpose I/O lines) and 4 control lines (for handshaking and interrupt generation). The directions for all 16 general lines (PA0-7, PB0-7) can be programmed independently. The control lines can be programmed to generate interrupts, automatically generate handshaking signals for devices on the I/O ports, or output a plain high or low signal.
In 1976 Motorola switched the MC6800 family to a depletion-mode technology to improve the manufacturing yield and to operate at a faster speed. The Peripheral Interface Adapter had a slight change in the electrical characteristics of the I/O pins so the MC6820 became the MC6821.[1]
The MC6820 was used in the Apple I to interface the ASCII keyboard and the display.[2] It was also deployed in the 6800-powered first generation of Bally electronic pinball machines (1977-1985), such as Flash Gordon[3] and Kiss.[4] The MCS6520 was used in the Atari 400 and 800[5] and Commodore PET[6] family of computers (for example, to provide four joystick ports to the machine). The Tandy Color Computer uses two MC6821s to provide I/O access to the video, audio and peripherals.[7]
Referencesedit
Leventhal, Lance A. (1986). 6502 Assembly Language Programming 2nd Edition. Osborne/McGraw-Hill. ISBN0-07-881216-X.
^Advanced Information: 1.5 and 2.0 MHz Components for the M6800 Microcomputer System. Austin, Texas: Motorola Semiconductor Products. April 1977. pp. 4–6. ADI-429. The MC6820 became the MC6821 because the electrical characteristic of PA0–7 and PB0–7 pins changed slightly. The typical Input High Current went from -250 μAdc to -400 μAdc and the Input Low Current went from 1.0 mAdc to 1.3 mAdc.
^(PDF). 1976. p. 7. Archived from the original (PDF) on 2011-05-19. Retrieved 2016-03-05.
peripheral, interface, adapter, peripheral, integrated, circuit, providing, parallel, interfacing, microprocessor, systems, motorola, mc6820, mc6821, 6520, configuration, irqa, irqb, description, editcommon, pias, include, motorola, mc6820, mc6821, technology,. A Peripheral Interface Adapter PIA is a peripheral integrated circuit providing parallel I O interfacing for microprocessor systems Motorola MC6820 and MC6821 Peripheral Interface Adapters MOS 6520 PIA pin configuration Vss 1 40 CA1 PA0 2 39 CA2 PA1 3 38 IRQA PA2 4 37 IRQB PA3 5 36 RS0 PA4 6 35 RS1 PA5 7 34 RES PA6 8 33 D0 PA7 9 32 D1 PB0 10 31 D2 PB1 11 30 D3 PB2 12 29 D4 PB3 13 28 D5 PB4 14 27 D6 PB5 15 26 D7 PB6 16 25 E PB7 17 24 CS1 CB1 18 23 CS2 CB2 19 22 CS0 Vcc 20 21 R W Description editCommon PIAs include the Motorola MC6820 and MC6821 and the MOS Technology MCS6520 all of which are functionally identical but have slightly different electrical characteristics The PIA is most commonly packaged in a 40 pin DIP package The PIA is designed for glueless connection to the Motorola 6800 style bus and provides 20 I O lines which are organised into two 8 bit bidirectional ports or 16 general purpose I O lines and 4 control lines for handshaking and interrupt generation The directions for all 16 general lines PA0 7 PB0 7 can be programmed independently The control lines can be programmed to generate interrupts automatically generate handshaking signals for devices on the I O ports or output a plain high or low signal In 1976 Motorola switched the MC6800 family to a depletion mode technology to improve the manufacturing yield and to operate at a faster speed The Peripheral Interface Adapter had a slight change in the electrical characteristics of the I O pins so the MC6820 became the MC6821 1 The MC6820 was used in the Apple I to interface the ASCII keyboard and the display 2 It was also deployed in the 6800 powered first generation of Bally electronic pinball machines 1977 1985 such as Flash Gordon 3 and Kiss 4 The MCS6520 was used in the Atari 400 and 800 5 and Commodore PET 6 family of computers for example to provide four joystick ports to the machine The Tandy Color Computer uses two MC6821s to provide I O access to the video audio and peripherals 7 References editLeventhal Lance A 1986 6502 Assembly Language Programming 2nd Edition Osborne McGraw Hill ISBN 0 07 881216 X Advanced Information 1 5 and 2 0 MHz Components for the M6800 Microcomputer System Austin Texas Motorola Semiconductor Products April 1977 pp 4 6 ADI 429 The MC6820 became the MC6821 because the electrical characteristic of PA0 7 and PB0 7 pins changed slightly The typical Input High Current went from 250 mAdc to 400 mAdc and the Input Low Current went from 1 0 mAdc to 1 3 mAdc Apple 1 Operation Manual PDF 1976 p 7 Archived from the original PDF on 2011 05 19 Retrieved 2016 03 05 Flash Gordon Manual Bally 1981 p 22 Kiss Manual Bally 1979 p 22 Sams Computerfacts Technical Service Data Atari 800 PDF November 1984 p IV West Raeto Collin January 1982 Programming the PET CBM COMPUTE Books ISBN 0 942386 04 3 Retrieved 2020 04 05 Chris Lomont July 2006 Chris Lomont s Color Computer 1 2 3 Hardware Programming PDF www lomont org Software Misc CoCo Lomont CoCoHardware pdf Retrieved 5 May 2020 nbsp This computing article is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Peripheral Interface Adapter amp oldid 1223885154, wikipedia, wiki, book, books, library,
