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The valid function code mnemonics are:
The BR, GD, GO, and GT commands set the valid function codes to either a user program (UP)
or supervisor program (SP). When execution is started via GO, GN, or GD, the default address
space is determined by bit 13 (the S-bit) of the status register (SR). When set, SP is used; when
cleared, UP is used. By specifying a function code with GO, GT, or GD command, the SR S-bit
is forced to the correct state before execution begins.
For the GT command, the temporary breakpoint is set using the function code specified, or it
defaults to SP or UP, depending on the state of the S-bit in the SR.
Though function codes are supported, the BCC hardware does not require function codes to
operate.
EXAMPLE
CPU32Bug>m 5000^ud<CR>
00005000^UD
CPU32Bug>
M68CPU32BUG/D REV 1
Function
Code Mnemonic
0
F0
1
UD
2
UP
3
F3
4
F4
5
SD
6
SP
7
CS
To change data at location $5000 in the user data space.
0000
?
1234.<CR>
DEBUG MONITOR DESCRIPTION
Description
Unassigned, reserved
User Data
User Program
Unassigned, reserved
Unassigned, reserved
Supervisor Data
Supervisor Program
CPU Space Cycle
2-13
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