Service manual

Service Manual
Option 110
loop STMIA r9,{r11,r12};write and read multiple
LDMIA r9,{r1,r2 ;words
STMIA r10{r11,r12
LDMIA r10,{r1,r2}
ADDS r8, r8, r7
BCS loop
Option 111
loop STMIA r9,{r11,r1 2} ;store multiple words
STRB r11,[r10] ;write byte
STR r12,[r9] ;write words
LDMIA r9,{r1,r2}
LDRB r1,[r10]
LDR r1,[r9] ;read single and
ADDS r8, r8, r7 ;multiple words
BCS loop
Note that R7 holds the value -1, and is used to
decrement the loop counter in R8. The pattern of using
bit zero to define a word or byte operation is broken on
options 101 and 111, since there is no load multiple byte
instruction. These options instead contain a mixture of
byte, word and multiple word operations. The second
address (R10) is used only for byte operations, and so
need not be a word-aligned value.
Probe SWIs
The *commands documented above are built around the
simple operations described in the debug protocol. The
low-level operations used to write commands to the
target system are made available by the Probe module
as a set of SWIs, described on the following pages.
Probe_Reset
(SWI &C8000)
Reset the target machine
On entry
R0 = Reset repetition period in microseconds
00000000 for single-shot reset
FFFFFFFF for permanent reset
On exit
R0 = result status
0 if the SWI succeeded
pointer to error block if the SWI failed
Interrupts
Unchanged
Processor mode
SVC mode
Re-entrancy
Not re-entrant (to safeguard hardware state)
Use
This is used to force the target system Reset line
active cyclically, permanently or transiently.
Related SWIs
Probe_Write, Probe_Read, Probe_Run
Related vectors
None
Part 5 - Main PCB fault diagnosis Issue 2, June 1991 5-17