HP MC68040 User Manual page 692

Chapter 18: Connecting the Emulator to a Target System
Installing Emulator Features
When a software breakpoint instruction is executed, the processor initiates a
breakpoint-acknowledge cycle. This cycle signals the start of an entry into the
monitor. From this point on, stacking and the vector fetch proceed the same as for
a break entry. Unlike the interrupt-acknowledge cycle, the
breakpoint-acknowledge cycle is shown to the target system.
tck -u
tsto any
tg stat=11xxxxxxxx1x000xy
t
r 8
Line
-----
-4
-3
-2
-1
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
The only unique part of a breakpoint entry is the breakpoint-acknowledge cycle so
any problems will probably be related to this cycle. Because the emulator
internally responds to this cycle, it is not necessary for the target system to respond
to it. If the target system responds to this cycle with any wait states, the emulator
may become out of sync with the target system because the emulator terminates this
cycle immediately. If this causes a problem, it will show up on the cycle
immediately following the breakpoint-acknowledge cycle.
662
addr,H 68040 Mnemonic
-------- ------------------------------------------
00000008 $484F0000 log sprog long read
0000000c $00000000 log sprog long read
00000010 $01000000 log sprog long read
00000014 $00000000 log sprog long read
00000000 $41------
00000200 $0000040B mmu twalk data long read
00000400 $0000060B mmu twalk data long read
0000063c $0000F01B mmu twalk data long read
0000f0ee $----0010 phy sdata word write
0000f0ea $----0000 phy sdata word write
0000f0ec $0008---- phy sdata word write
00000200 $0000040B mmu twalk data long read
00000400 $0000060B mmu twalk data long read
00000600 $0000009F mmu twalk data long read
00000010 $000016A2 phy sdata long read
0000f0e8 $2700---- phy sdata word write
00000200 $0000040B
00000400 $0000060B
00000600 $0000101b
000016a0 $007E2F0D phy sprog long read
000016a4 $4BFAFA73 phy sprog long read
bkpt ack (buserror)
twalk prog long read
twalk prog long read
twalk prog long read
<- bkpt fetch
<- acknowledge
<- twalk stack
<- stack format
<- stack PC high
<- stack PC low
<- twalk vector
<- vector fetch
<- stack SR
<- twalk monitor
<- monitor