Motorola MVME162 manual VMEbus Interface and VMEchip2, Interfaces, Serial Communications Interface

Functional Description

is an 8 bit device; however, the interface provided by the MCchip supports 8- bit, 16-bit, and 32-bit accesses to the MK48T08. Refer to the MCchip descrip- tion in the MVME162 Embedded Controller Programmer’s Reference Guide and to the MK48T08 data sheet for detailed programming and battery life information.

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VMEbus Interface and VMEchip2

The local bus to VMEbus interface and the VMEbus to local bus interface are provided by the optional VMEchip2. The VMEchip2 can also provide the VMEbus system controller functions. Refer to the VMEchip2 description in the MVME162 Embedded Controller Programmer’s Reference Guide for detailed programming information.

Note that the ABORT switch logic in the VMEchip2 is not used. The GPI inputs to the VMEchip2 which are located at $FFF40088 bits 7-0 are not used. The ABORT switch interrupt is integrated into the MCchip ASIC at location $FFF42043. The GPI inputs are integrated into the MCchip ASIC at location $FFF4202C bits 23-16.

I/O Interfaces

The MVME162 provides onboard I/O for many system applications. The I/O functions include serial ports, IndustryPack (IP) interfaces, optional LAN Ethernet transceiver interface, and optional SCSI mass storage interface.

Serial Communications Interface

The MVME162 uses a Zilog Z85230 serial communications controller to implement the two serial communications interfaces. Each interface supports CTS, DCD, RTS, and DTR control signals; as well as the TxD and RxD transmit/receive data signals, and TxC/RxC synchronous clock signals.

The Z85230 supports synchronous (SDLC/HDLC) and asynchronous protocols. The MVME162 hardware supports asynchronous serial baud rates of 110b/s to 38.4Kb/s.

The Z85230 supplies an interrupt vector during interrupt acknowledge cycles. The vector is modified based upon the interrupt source within the Z85230. Interrupt request levels are programmed via the MCchip. Refer to the Z85230 data sheet listed in this chapter, and to the MCchip Programming Model in the MVME162 Embedded Controller Programmer’s Reference Guide, for information.

MVME162 Serial Port 1

The A port of the Z85230 is interfaced as DCE (data circuit-terminating equipment) with the EIA-232-D interface and is routed to:

MVME162IG/D2 1-15