AN000018.TXT Advanced Communication Board Developer's Toolkit 1995 ---------------------------------------------------------------------- ---------------------------------------------------------------------- Subject: Differences between ACB products. This application note briefly describes each ACB product. For additional product details, please contact technical support at the numbers listed in the README.TXT file located in the root directory of this diskette. ACB-II The ACB-II is the first member of the Advanced Communication Board Family. This versatile single channel adapter can be configured for RS-232 or RS-422 operation. This flexible feature of the ACB-II makes it great for a development or prototype environment. The ACB-II can communicate with RS-485. This specification is used widely in multi-drop networks. The ACB-II will allow IRQ choices of 3, 4, or 5 and provides eight different I/O addresses to the developer. Unlike other ACB adapters, the ACB-II does not provide full modem control signals. The ACB-II supports a single DB-25 connector. These characteristics make the ACB-II an excellent low to medium range communications solution. ACB-III The ACB-III, like the ACB-II provides an RS-232 interface. The ACB-III supplies the user with two full channels of RS-232 communications. This adapter will allow the developer to utilize both channels of the SCC in an RS-232 based application. The ACB-III supports full modem control signals on both channels. Full duplex DMA is an enhancement over the ACB-II. The ACB-III can reside at any I/O location 0 through 3FF hexadecimal. DMA channels 1 and 3 and IRQ choices 2/9, 3, 4, and 5 are provided to the user. The ACB-III is an ideal solution for applications that require one or two channels of high speed RS-232 synchronous or asynchronous communications. ACB-IV The ACB-IV is the next member of the ACB product family. This adapter is very similar to the ACB-III in configuration options and available systems resources. The main difference between the ACB-III and the ACB-IV is that the ACB-IV is RS-422, not RS-232. The ACB-IV provides two channels of RS-422 signal levels on a EIA-530 specified connector. The ACB-IV, much like the ACB-III offers full-duplex DMA, full modem control signals, IRQ options 2/9, 3, 4, and 5, and DMA channels 1 and 3. The ACB-IV, like the ACB-II can be used with a RS-485 interface. The ACB-IV, because of the differential drive capabilities of RS-422 and 485 can communicate at much higher data rates than the ACB-III. The ACB-III is limited by the RS-232 specification and the RS-232 line drivers and receivers. The RS-422 interface of the ACB-IV gives the user two channels of error free, high speed, long distance communications. ACB-V The ACB-V is very similar to the ACB-III and ACB-IV. The ACB-V provides two channels of CCITT V.35 that can be used for synchronous or asynchronous communications. This ACB adapter provides the user with two channels of V.35 with modem control, IRQs 2/9, 3, 4, and 5, and DMA channels 1 and 3 as configuration options. The ACB-V, like the ACB-III and ACB-IV will support full duplex DMA transfers. The ACB-V, unlike the ACB-III and ACB-IV, will not generate a clock signal, because the CCITT V.35 specification does not specify a clock output signal for a V.35 DTE. If an output clock is required signal with the V.35 interface, please refer to the ACB-VI or the ACB-MP. The ACB-V is compatible with CCITT V.36 and V.37. ACB-VI The next member of the ACB product family combines many of the key features of the earlier ACB family members. The ACB-VI supplies the user with one asynchronous RS-232 port and one synchronous / asynchronous user selectable RS-232 / RS-422 / RS-485 / EIA-530 / CCITT V.35 / MIL-188-114 / MIL-188-C high speed communication port. Channel A of the SCC is dedicated to synchronous / asynchronous communications. This port supports full duplex DMA on channels 0, 1, 2, or 3. User selectable IRQs include 2/9, 3, 4, 5, 7, 10, 11, 12, and 15. When using the CCITT V.35 interface of the ACB-VI, channel A of the SCC can supply a clock signal at V.35 signal levels. This is not normally available with other V.35 DTE devices. The ACB-VI provides many additional configuration options to the user and developer, making the ACB-VI the ideal solution for an application that requires interfaces to multiple protocols. ACB 530 The ACB 530 is very similar to the ACB-IV. The ACB 530 supports two full EIA-530 channels of communications, much like the ACB-IV. The ACB 530 offers additional IRQ and DMA options that the ACB-IV does not offer. The ACB 530 can be configured for IRQ 2/9, 3, 4, 5, 7, 10, 11, 12, and 15. This adapter can be configured for DMA channels 0, 1, 2, or 3. One feature of this adapter that is not available on any other ACB adapter is that both channels can operate in a full duplex DMA mode. This allows both channels to transmit and receive at the same time. This feature makes the ACB 530 suitable for medium to high range synchronous applications. ACB-MP The ACB-MP is the only ACB adapter that can be used on a Micro Channel Architecture (MCA) bus. This feature allows existing applications based on an ACB family member to be ported to a computer system with a Micro Channel Architecture. Computer systems based on the RS/6000, DEC Alpha, Power PC RISC Processor, and the Intel Pentium all utilize the Micro Channel bus. The ACB-MP provides the MCA computer with one high speed synchronous / asynchronous user selectable RS-232 / RS-422 / RS-485 /EIA-530 / CCITT V.35 interface. When using the ACB-MP in V.35 mode the user has the option of supplying a V.35 output clock. All address and IRQ options are selected by the MCA Programmable Option Select (POS) setup. Please note that the ACB-MP does not support DMA however the MCA bus will allow considerably higher interrupt driven throughput than the ISA bus. ACB-104 The ACB-104 was designed to allow existing ACB based applications to be used on an expansion bus other than the PC ISA bus. The ACB-104 was designed to function on the PC/104 bus. This bus is used in embedded applications because of its small form factor. The ACB-104 features RS-232 and RS-422/485 versions that have IRQ 2/9, 3, 4, 5, and 7 as selectable interrupts. The ACB-104 will support full duplex DMA, however the ACB-104 is a single channel interface. These features make the ACB-104 an ideal solution for embedded synchronous / asynchronous applications. MAXPORT The MAXPORT ACB adapter was created to aid the developer in porting their applications from the Apple Macintosh to an ISA architecture. The Apple Macintosh utilizes the 8530 SCC as its communication controller. This ACB adapter for the PC was designed with the same interface that the Apple Macintosh uses allowing Macintosh peripherals to communicate with the PC. This adapter utilizes features of the SCC in the same manner the Macintosh does. The MAXPORT does not use DMA. IRQs that are available are 2/9, 3, 4, 5, 7, 10, 11, 12, and 15. ACB 188 The ACB 188 was designed to provide the PC with two high speed Sync / Async ports for Digital Radio communications. A unique feature of the ACB 188 is the capability to receive single ended transmissions or differential transmissions. The ACB 188 provides Push-to-Talk circuitry allowing the PC to interface with various Digital Radios. The ACB 188 can be configured for IRQs 2/9, 3, 4, 5, 6, 7, 10, 11, 12, and 15. The ACB 188 has user selectable MIL 188/114, MIL 188/C or MIL 188/220 interface. The ACB 188 does not use DMA. PC-ACB The PC-ACB cards provide a single PCMCIA Synchronous serial link to devices that require high speed mobile communications. The PC-ACB cards are available as RS-422/485 or RS-232 interface. Hot swapping allows the cards to inserted and removed from the socket while the computer is powered up. The PC-ACB uses an ESCC (Zilog 85233) and has a 16MHz clock. The PC-ACB has a single input clock (RTC) and a single output clock (TSET). Due to the small size of the PCMCIA Type II cards and limitations in the PCMCIA Release 2.1 specification, the PC-ACB does not support DMA. ACB 56 The ACB 56 provides the PC with two communications ports, a single RS-232 or V.35 high speed Synchronous / Asynchronous channel and a single RS-232 Asynchronous CSU/DSU interface channel. The RS-232/V.35 selectable port can be used as the high speed CSU/DSU data pipe, providing data rates in excess of 56K and 64Kbps. The Async RS-232 port is targeted as a low speed analog dialog port or for CSU/DSU status monitoring. The ACB 56 can be configured for IRQ 2/9, 3, 4, 5, 7, 10, 11, 12, and 15. This adapter can also be configured for DMA channels 1 and 3.