Keil MCB517AC, Руководство пользователя

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MCB517AC Evaluation Board User’s Guide 31
Code memory
Monitor
EPROM
Bank 0
Xdata memory
00000H
0FFFFH
0F800H
0F700H
On-chip XRAM
*3
CAN-contoller
User Chip select
0F600H
0E800H
unused
Restricted Area
*1
Common
Monitor
EPROM
Bank 1
Common
Monitor
EPROM
Bank 4
Common
Monitor
EPROM
Bank 5
Common
...
08000H
User XDATA Area
0D200H
*2
*1
Since this XDATA area is ‘von-Neumann’ wired, write accesses also modify
the CODE space. Locate your XDATA segments after the end of your
program and constant segments!
*2
The banked monitor 51 typically requires 256 bytes of external memory
(0E700h - 0E7FFh) in bank 5. Only when you enable ‘Record trace’ in the
dScope ‘Commands’ pull down menu, 5.25 KB additional memory is
required to hold the trace information.
*3
The 2Kb on-chip XRAM is available only with an 80C517A from X:F800h-
FFFFh when the SFR-bit XMAP0 is cleared
Monitor Data & Interrupt Vectors
The 8051 monitor uses no interrupt vectors. Only, if you have enabled the serial
interrupt, you need to reserve the interrupt vector space for the internal interrupt
0 or serial interrupt. The 8051 monitor uses the address space X:0xE700 ..
X:0xE7FF for monitor data. If you enable “Record Trace”, then the address
space X:0xD300 .. X:0xE7FF is used for monitor data. The complete
CODE/XDATA space is von-Neumann wired, so that accesses to the XDATA
space modify also the data in the CODE space.