EZ80L92MCU Datasheet, PDF (198/241 Pages) Zilog, Inc. – eZ80Acclaim Flash Microcontrollers

eZ80L92 MCU
Product Specification
183
ZDI Read Memory Register
When a Read is executed from the ZDI Read Memory register, the eZ80L92 fetches the
data from the memory address currently pointed to by the program counter, PC; the pro-
gram counter is then incremented. In Z80 MEMORY mode, the memory address is
{MBASE, PC[15:0]}. In ADL MEMORY mode, the memory address is PC[23:0]. Refer
to the eZ80 CPU User Manual (UM0077) for more information regarding Z80 and ADL
MEMORY modes. The program counter, PC, increments after each data Read. However,
the ZDI register address does not increment automatically when this register is accessed.
As a result, the ZDI master can read any number of data bytes out of memory through the
ZDI Read Memory register. See Table 106.
Table 106. ZDI Read Memory Register (ZDI_RD_MEM = 20h in the ZDI Register
Read-Only Address Space)
Bit
Reset
CPU Access
Note: R = Read-only.
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
R
R
R
R
R
R
R
R
Bit
Position
[7:0]
zdi_rd_mem
Value Description
00h–
FFh
8-bit data read from the memory address indicated by the
CPU’s program counter. In Z80 MEMORY mode, 8-bit
data is transferred out from address {MBASE, PC[15:0]}.
In ADL Memory mode, 8-bit data is transferred out from
address PC[23:0].
PS013012-1004
PRELIMINARY
ZiLOG Debug Interface