Zilog Z80195 - Manual (Page 27)

Z80185/195 D EVELOPMENT K IT
U SER ' S M ANUAL
3-7 UM951800100
Z ILOG
Edit/Display I/O Data [E]
This command allows editing or display of registers in I/O space. First, the program asks for a starting
address, which can be 16 bits. Then it asks for the number of registers to display. If you enter "0" or
just a , you enter Editing mode. If you enter a nonzero value, that number of I/O registers
will be displayed following the starting address.
Example of Display Mode:
Z80185 > Edit/Display Starting at I/O Register: 40
Display How Many Bytes (just CR to Edit): 10
0040 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78 78
Z80185>
In Editing mode, the program displays what it reads from each I/O location. Entering a hex value
followed by a valid terminating character (not including ) will make the program write the
entered value to the location. The program recognizes the following terminating characters:
Does not store a preceding value and returns to the command prompt.
. Stores a preceding value if any and returns to the command prompt.
= Stores a preceding value if any, stays at the same location, re-reads and re-
displays.
CR,tab,Space,+,> Stores a preceding value if any, and go to the next location.
-,<,^ Stores a preceding value if any, and go to previous location.
In addition to these, a backspace character after a hex character “unenters” one hex character.
With the original Z80 Family, I/O addresses were 8-bit wide and thus I/O space was 256 bytes long.
In the Z180 Family (this monitor program), I/O addresses are treated as 16-bits wide, thus I/O space
contains 65,536 bytes. The Z180 peripherals appear only on the first 256-byte page, in addressees
0000 -003F unless they have been reallocated by software to 0040-007F or 0080-00BF. The unique
peripherals of the Z80185/195 may appear in every page or only the first page depending on a
programmable bit in the I/O register.