Programming Model
http://www.mcg.mot.com/literature
3-13
3
SCCIT<1:0>These bits define the IACK daisy chain time for the SCC
chips. They must be set based on the number of SCC
devices.
!
Caution
These bits must be initialized to 01 for the MVME172 boards
because they contain two Z85230 devices.
Interrupt Vector Base Register
The interrupt vector base register is an 8-bit read/write register that is used
to supply the vector to the MC68xx060 during interrupt acknowledge
cycles. Only the most significant four bits are used. The least significant
four bits encode the interrupt source during the acknowledge cycle.
The exception to this is that after reset occurs, the interrupt vector passed
is $0f, which remains in effect until a write is generated to the vector base
register.
A normal read access to the vector base register yields the value $0f if the
read happens before it has been initialized. A normal read access yields all
0s on bits 0-3 and the value that was written on bits 4-7 if the read happens
after the register has been initialized.
SCCIT<1:0>
Number of Z85230s
00
1
01
2
10
3
11
4
ADR/SIZ
$FFF42000 (8 bits)
BIT
7
6
5
4
3
2
1
0
NAME
IV7
IV6
IV5
IV4
IV3
IV2
IV1
IV0
OPER
R/W
R/W
R/W
R/W
R
R
R
R
RESET
0 PL
0 PL
0 PL
0 PL
1 PL
1 PL
1 PL
1 PL
Содержание MVME172
Страница 1: ...MVME172 VME Embedded Controller Programmer s Reference Guide VME172A PG2 Edition of February 1999 ...
Страница 6: ...Place holder ...
Страница 18: ...xviii ...
Страница 78: ...1 60 Computer Group Literature Center Web Site Board Description and Memory Maps 1 ...
Страница 332: ...5 42 Computer Group Literature Center Web Site MCECC 5 ...
Страница 336: ...A 4 Related Documentation A ...
Страница 340: ...VMEchip2 Tick Timer 1 Periodic Interrupt Example B 4 Computer Group Literature Center Web Site B ...
Страница 352: ...Index IN 12 Computer Group Literature Center Web Site I N D E X ...
Страница 354: ......