Specifications

Getting Started
The dual port RAM is a 32 Kbyte RAM populated on the ZT 8832. It
is shown on both local and STD bus memory maps because, even
through it is the same physical memory, it is accessible from both the
local CPU and the STD CPU. The address range of the dual port
RAM as seen by the local CPU is fixed from 80000 through 87FFFh.
The address range of the dual port RAM as seen by the STD bus CPU
is jumper selectable to any 32 Kbyte memory block within a 1 Mbyte
address range of an STD bus CPU. Some STD bus microprocessors
support a 16 Mbyte address range by generating a 24-bit memory
address. The ZT 8832 can be configured to jumper select the dual port
RAM into any 32 Kbyte memory block within this 16 Mbyte address
range. As shipped, the address range is XC8000 through XCFFFFh.
The local RAM consists of two contiguously mapped 32-pin JEDEC
sockets. The sockets are shipped to support 32 Kbyte RAM devices.
Jumper options also permit both sockets to support 128 Kbyte
devices, and one of the sockets to support a 512 Kbyte device. Please
note that while the 512 Kbyte RAM is supported by the ZT 8832, it
may not be currently available. The access time of the local RAM
devices must not be greater than 250 ns. This RAM is not addressable
by the STD bus CPU.
XFFFFFh
XD0000h
XCFFFFh
X00000h
Not Used
Dual Port RAM
Not Used
XC8000h
XC7FFFh
Figure 2–4. STD Bus CPU Memory.
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