MVME5100 Single Board Computer Programmer's Reference Guide

IPMC7xx ISA Bus Resources
Z85230 ESCC and Z8536 CIO Registers and Port Pins
Z8536/Z85230 Registers
The Z85230 ESCC is used to provide the two sync/async serial ports on
some MVME5100 series models. The PCLK which can be used to obtain
the baud rates, is 10 MHz. Refer to the SCC User’s Manual for
programming information on the Z85230 ESCC device.
The Z8536 CIO is used to provide the modem control lines not provided
by the Z85230 ESCC and a method to inquire the module ID of the two
sync/async serial ports that reside on the MVME761 module. Refer to the
Z8536 Data Sheet for programming information.
Accesses to the Z8536 CIO and the Z85230 ESCC are accomplished via
Port Control and Port Data Registers. The PCLK to the Z8536 is 5 MHz.
Also, a Pseudo IACK Register is also defined to retrieve interrupt vectors
from these devices. The Z8536 CIO has higher priority than the Z85230
ESCC in the interrupt daisy chain. The following list the registers
associated with accessing these two devices:
Table 1-19. Z8536/Z85230 Access Registers
PCI I/O Address Function
0000 0840 Z85230: Port B (Serial Port 4) Control
0000 0841 Z85230: Port B (Serial Port 4) Data
0000 0842 Z85230: Port A (Serial Port 3) Control
0000 0843 Z85230: Port A (Serial Port 3) Data
0000 0844 Z8536 CIO: Port C’s Data Register
0000 0845 Z8536 CIO: Port B’s Data Register
0000 0846 Z8536 CIO: Port A’s Data Register
0000 0847 Z8536 CIO: Control Register
0000 084F Z85230/Z8536 Pseudo IACK
http://www.motorola.com/computer/literature 1-35
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