Mostek z80 - Page 48

3-12
Format
(3) is used to set a hardware breakpoint.
only one hardware
breakpoint is allowed and when a new hardware breakpoint is set the previous
hardware breakpoint is cleared. The hardware breakpoint does not replace
any of the users code and is functional in RCXV1 as well as RAM. The hardware
breakpoint may be set anywhere in memory (program or data) and will be
recognized. If the hardware breakpoint is set on subsequent bytes of an
instruction, one additional instruction may be executed after the
breakpoint.
Format (4) is used to clear a breakpoint at a specific address. Both
hardware and
software breakpoints (if any) are cleared. If no breakpoint is
set at the specified address, the command has no effect.
Format (5) is used to clear all breakpoints (hardware, software, or timer,
if any). If no breakpoints are set then the command has no effect.
Format (6) is used to specify the History or hardware breakpoint options.
When this fonnat is entered, a prompt sequence is started which allows
the user to examine and/or update the following six options:
1. The first option allows the user to examine/update the twenty-four
bit trigger word. The user may specify either 1 (high), 0 (low) or X (don't
care) for each bit of the trigger word. The character (SP) will advance to
the next bit of the trigger word while (8S) will backup to the previous bit.
The left most eight bits of the trigger word (PA7-PA0) corresponds to the A
PROBES on the Buffer module. The probes are color coded to standard
resistor color codes (0-black, I-brown, 2-red, 3-orange, 4-yellow, 5-green,
6-blue, 7-violet, 8-grey). The right most sixteen bits of the trigger word
(AI5-A0) corresponds to the Target Z80 address bus.