CS82C55A - 24-Bit CMOS Programmable I/O Interface
MPN： CS82C55A ✓ 啟用中CS82C55A 概覽
A programmable peripheral interface is an interface IC used to extend a limited microprocessor bus with general-purpose digital I/O. It belongs to the parallel interface and interface-controller hierarchy, where a system CPU handles configuration while the CS82C55A manages data transfer, handshaking, and port direction control. The CS82C55A divides its 24 lines into two independently controlled groups of 12, allowing each group to operate as an 8-bit port with four control lines, as two 4-bit ports, or as individual bit-oriented channels.
The device's three main operating modes provide design flexibility. Mode 0 supports strobed input or output operation, Mode 1 provides programmed interrupt and handshake signaling for peripheral data transfer, and Mode 2 supports bidirectional bus operation on one port. Each of the 24 lines can be configured as input or output, and the two 4-bit port-control signals can operate in either strobed or interrupt-driven form. This makes the part useful when a processor needs more parallel lines than are available on its native bus.
Manufactured using a self-aligned silicon-gate CMOS process identified as Scaled SAJI IV, the CS82C55A provides static CMOS operation with low operating power. Its 5 V supply arrangement and 8 MHz clock capability allow it to interface with the timing envelope of the microprocessor families cited in the manufacturer documentation. The PLCC-44 package also supports leaded-board assembly, although board layout must preserve the device's exact pin arrangement and supply requirements.
Typical uses include industrial control panels, printer and peripheral interfaces, general-purpose data acquisition, legacy industrial equipment, and embedded systems that retain an 8255A-compatible interface. The part is especially useful where configurable input, output, and handshake behavior is preferable to a fixed-purpose I/O expander. Firmware must configure the control word before each operating-mode change because the mode registers are write-only and do not retain their contents after reset.
A key design consideration is verifying the original board's signal direction, reset state, and timing assumptions rather than assuming that every 8255A implementation is electrically identical. Confirm the supply voltage, clock source, control-word sequence, and processor handshake signals against the manufacturer datasheet. If replacing an older device, check whether its board uses an 8255-compatible clock and whether any external logic depends on a particular mode-change transition.
This page consolidates the manufacturer's functional description, package and interface specifications, qualified drop-in references, and practical implementation guidance to support component identification, PCB reuse, and replacement planning.
直接替換替代品，適用於 CS82C55A — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
CS82C55A-5Z
✅ 直接替換📋 參考替代品（不在目錄中）
CS82C55AZ96
✅ 直接替換📋 參考替代品（不在目錄中）
IS82C55A-5
✅ 直接替換📋 參考替代品（不在目錄中）
CS82C55
✅ 直接替換📋 參考替代品（不在目錄中）
CS82C55A-596
✅ 直接替換📋 參考替代品（不在目錄中）
CS82C55A 規格
| Product Type | CMOS Programmable Peripheral Interface |
| 功能 | General-purpose programmable parallel I/O interface |
| Number of I/O Pins | 24 pins |
| I/O Grouping | 2 groups of 12 pins |
| 資料匯流排寬度 | 8 bits |
| Operating Modes | 3 modes |
| 供應電壓 | 5 V |
| Maximum Interface Clock | 8 MHz |
| Process Technology | Self-aligned silicon-gate CMOS, Scaled SAJI IV |
| 封裝 | 44-pin PLCC |
| Package Dimensions | 16.58 mm x 16.58 mm |
| 安裝類型 | Surface Mount |
| Microprocessor Compatibility | 80C86, 80C88, and other microprocessors |
| Circuit Design | Static CMOS |
| Operating Power | Low operating power |
CS82C55A 16.58 mm x 16.58 mm 腳位配置指南
CS82C55A（16.58 mm x 16.58 mm 封裝）的腳位配置。 腳位編號、功能與連接圖定義於製造商資料手冊中。請參閱該手冊以取得確切的封裝尺寸與焊接指引。
無詳細腳位定義資料： CS82C55A.
請參閱 資料表 以查看完整腳位配置。
典型應用
CS82C55A 適用於 6 應用s: Industrial Control Panels, Printer and Legacy Peripheral Interfaces, General-Purpose Data Acquisition, Embedded GPIO Expansion, Test Equipment Control Interfaces, Communication and Security Equipment.
Industrial Control Panels
The CS82C55A fits legacy industrial control panels that need more configurable parallel I/O than the host processor provides. Its 24 lines can be split into two 12-pin groups, with each group supporting Mode 0 strobed I/O, Mode 1 interrupt-driven handshaking, or Mode 2 bidirectional transfer. This allows status lamps, relay-control inputs, and operator-panel signals to share a processor bus while retaining the established 8255A control-word sequence. The 5 V supply and 8 MHz interface capability fit 80C86- and 80C88-class controllers, but timing, temperature, and lifecycle requirements should be checked against the enclosure environment.
推薦
Printer and Legacy Peripheral Interfaces
The CS82C55A is suitable for printer, card-reader, and other legacy peripheral interfaces built around the 8255A signal set. Mode 0 provides straightforward strobed data transfer, while Mode 1 adds interrupt and handshake capability for peripherals that cannot transfer data at the processor’s unrestricted bus rate. Its two independently configured port groups can separate data and control signals or connect one bidirectional channel and one unidirectional channel. The interface is especially useful when modernizing an existing assembly while retaining its processor bus and connector wiring; verify the original device’s clock requirements and configure the control word after every reset.
推薦
General-Purpose Data Acquisition
The CS82C55A can expand a microprocessor-based acquisition system with 24 individually configurable digital lines alongside its external counters and analog functions. Mode 0 supports sampled status inputs and latch-style outputs, and Mode 1 supplies handshake signals for slower external converters, counters, or fixture controls. The two port groups can be programmed separately, allowing an 8-bit data bus and four control lines to coexist with a second 8-bit data bus and four control lines. Its 8 MHz interface rate supports common embedded bus timing, but input levels, isolation, and sampling synchronization must be designed around the actual external hardware.
推薦
Embedded GPIO Expansion
The CS82C55A provides a practical path to expand the GPIO capacity of an embedded controller that already uses an 8255A-compatible bus. Its 24 lines are organized as two 12-pin ports, and each port can be operated in 8-bit, 4-bit, or bit-oriented configurations according to the selected mode. Mode 2 permits bidirectional use of Port A when a peripheral must both transmit and receive, while Mode 0 handles simpler input and output groups. The choice is most attractive when preserving a known bus interface and firmware structure is more valuable than redesigning the system around a serial I/O expander.
推薦
Test Equipment Control Interfaces
The CS82C55A can act as the parallel control interface in legacy test and measurement equipment driven by an 80C86, 80C88, or compatible processor. Mode 0 supports simple relay, indicator, and fixture-control outputs, while Mode 1 supports interrupt-driven acknowledgment from slower test peripherals. Because the two port groups are independently programmable, one group can handle an 8-bit instrument command while another provides individual handshake and status lines. The 5 V interface and 8 MHz clock align with established embedded control architectures, but designers should preserve the original timing and define reset states before connecting external fixtures.
推薦
Communication and Security Equipment
The CS82C55A can provide auxiliary parallel control and status signals in communication or security equipment that retains an 8255A-compatible expansion bus. Mode 1 is useful for modem, alarm, or peripheral modules requiring request and acknowledge signaling, while Mode 0 can operate discrete status and relay lines. The two port groups allow data and handshake signals to remain separated, helping simplify firmware and board routing. Compatibility with 80C86 and 80C88 processors supports serviceable industrial equipment, although modern security designs should add appropriate galvanic isolation and verify the device’s operating-temperature requirements at the system level.
推薦
推薦產品摘要
工程參考資料，適用於 CS82C55A — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | CS82C55A-5Z | CS82C55AZ96 | IS82C55A-5 | CS82C55 | CS82C55A-596 |
|---|---|---|---|---|---|---|
| Package | 44-pin PLCC | 44-pin PLCC | 44-pin PLCC | 44-pin PLCC | 44-pin PLCC | 44-pin PLCC |
| Brand | Renesas Electronics | Renesas Electronics | Renesas Electronics | Renesas Electronics | Renesas Electronics | Renesas Electronics |
| Product Type | CMOS Programmable Peripheral Interface | CMOS Programmable Peripheral Interface | CMOS Programmable Peripheral Interface | CMOS Programmable Peripheral Interface | CMOS Programmable Peripheral Interface | CMOS Programmable Peripheral Interface |
| Number of I/O Lines | 24 | 24 | 24 | 24 | 24 | 24 |
| Data Bus Width | 8 bits | 8 bits | 8 bits | 8 bits | 8 bits | 8 bits |
| Operating Modes | 3 modes | 3 modes | 3 modes | 3 modes | 3 modes | 3 modes |
| Processor Compatibility | 80C86, 80C88, and other microprocessors | 8255A-compatible microprocessor interface | 8255A-compatible microprocessor interface | 8255A-compatible microprocessor interface | 8255A-compatible microprocessor interface | 8255A-compatible microprocessor interface |
| Process Technology | Scaled SAJI IV self-aligned silicon-gate CMOS | CMOS | CMOS | CMOS | CMOS | CMOS |
主要差異化特點
- Industry-standard programmable parallel interface (對比PCA9555PWR)
- Direct compatibility with established microprocessor bus arrangements (對比PCF8574DWR)
- Independent configuration of two 12-line port groups (對比PCA9534PWR)
設計說明
Route the 8-bit data bus, read/write control, reset, clock, and port-control signals to match the original 8255A-compatible board arrangement. Keep the 44-pin PLCC footprint and pin numbering under direct control when replacing CS82C55A variants; the LCC/PLCC naming used by distributors does not remove the need to check lead geometry, pad dimensions, and orientation against the actual PCB footprint.
Program the control word after every reset and whenever changing a port between Mode 0, Mode 1, or Mode 2. The mode registers are write-only, so software cannot read back the current configuration. Also confirm whether a particular port direction is legal in the selected mode; attempting bidirectional operation in Mode 0 can produce incorrect results even though the external 24-line interface remains connected.
Use the manufacturer timing diagrams to establish setup and hold requirements for read/write, reset, clock, and port-control transitions at the system clock. The 8 MHz interface capability does not remove peripheral timing constraints. For Mode 1 handshakes, verify interrupt acknowledgment behavior and avoid polling faster than the peripheral can update its status signals, because the processor interface and external device may have different response times.
Provide a stable 5 V supply and follow the manufacturer’s decoupling recommendations directly at the device pins. Separate noisy peripheral return currents from sensitive processor ground paths, and use the port-control signals to disable external loads during reset when required by the system architecture. This prevents uncontrolled peripheral activity and reduces the chance of data-bus contention while the CS82C55A initializes.
合規資訊
No definitive RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals status is stated for the exact CS82C55A ordering configuration. The comparison listing marks the CS82C55 family as not RoHS-compliant, but that family-level marking does not establish the status of every suffix.
