Motorola CPCI-6115 - Manual (Page 131)

System I/O Memory Map Memory Maps
CPCI-6115 CompactPCI Single Board Computer Installation and Use (6806800A68D) 129
8.2.5 System I/O Memory Map
System resources including system control and status registers, NVRAM/RTC and the 16550
UART are mapped into a 1 MB address range assigned to Device Bank 1. The memory map is
defined in the following table:
All register descriptions follow a fixed convention. The possible operations for each bit within a
register are as follows:
R - The bit is a read only status bit.
R/W - The bit is readable and writable.
R/C - The bit is cleared by writing a one to itself.
W - The bit is a write only bit.
8.2.6 PCI Local Bus Memory Map
There are two PCI local buses on the CPCI-6115: PCI Bus 0.0 and PCI Bus 1.0. The only device
on PCI Bus 0.0 is PMC 2. The PCI devices on PCI Bus 1.0 are PMC 1, the CMD 646U2 IDE
controller and the Intel 21555 PCI-to-PCI bridge.
8.2.7 CompactPCI Memory Map
The CPCI-6115 uses the 21555 non-transparent PCI-to-PCI bridge to interface between the
local PCI bus and the CompactPCI bus. The 21555 is different from traditional PCI-to-PCI
bridges in that it uses address translation instead of a flat address map between primary and
secondary PCI buses. In the CPCI-6115 configuration, the primary bus is the CompactPCI bus
and the secondary bus is the CPCI-6115 local bus. Downstream transactions are those that are
initiated on the primary bus and are forwarded to the secondary bus. Upstream transactions are
those initiated on the secondary bus and forwarded to the primary bus.
Table 8-5 Device Bank 1 I/O Memory Map
Address Definition
F110 0000 System Control/Status Register 1
F110 0001 System Control/Status Register 2
F110 0002 System Control/Status Register 3
F110 0003 Geographic Address Register (CompactPCI)
F110 0004 PCI Presence Detect Register
F110 0005 Software Readable Header/Switch
F110 0006 Timebase Enable Register
F110 0008 System Interrupt Status Register
F110 0009 - F110 FFFF Reserved for onboard registers
F111 0000 - FF11 7FFF M48T37V NVRAM/RTC
F112 0000 - FF12 0FFF COM1 16550 UART
F112 1000 - FF12 1FFF COM2 16550 UART