Xerox Alto I User Manual

Alto Hardware Manual
FIELDS:
0-4.
5-8
9-11
12-15
16-19
20
APPENDIX A - MICROINSTRUCTION SUMMARY
RSELECT
21
22-31
ALUF
BS
Fl*
F2*
LOADT
LOADL&M*
NEXT
*High-order bit complemented by RDRAM
and WRTRAM.
All subsequent numbers on this page are in octal.
ALUF:
0: BUS
1: T
2: BUS OR T*
3: BUS ANDT
*Loads T from ALU output
BUS SOURCE (standard):
0: ~RLOCATION
1: RLOCA TION ~
2: None (BUS~-I)
3: (task-specific)
Fl (standard):
0: -
1: MAR~
2: TASK
3: BLOCK
F2 (standard):
0: -
·1: BUS=O
2: SH( 0
3: SH = 0
BUS SOURCE
(task-specific):
4: BUS XOR T
5: BUS+l*
6: BUS-l*
7: BUS+T
4: (task-specific)
5: ~MD
6: ~MOUSE
7: ~DISP
4: ~L LSH 1
5: ~L RSH 1
6: ~L LCY 8
7:
~CONSTANT
4: BUS
5: ALUCY
6: MD+-
7: ~CONSTANT
4.16 7
10: BUS-T
11: BUS-T-l
12: BUS+T+l*
13: BUS+SKIP*
RAM
o
CPU
KSEC,KWD
EfHER Related
14:
BUS.T*
15: BUS AND NOT T
16:
UNDEFINED
17: UNDEFINED
3: ~SLOCATION
4: SLOCATION~
~KSTAT
~KDATA
EIDFCT
+-SLOCATION
SLOCATION+-
Fl (task-specific):
0
4, 16
7 11
12
13
14
CPU
KSEC,KWD EfHER DWT
CURT DHT DVT
10: SWMODE
11:
·WRTRAM
STROBE
12: RDRAM
KSTAT+-
13:
RMR+-
INCRECNO
ELFCT
14:
-
CLRSTAT EPFCT
15:
ESRB~
KCOMM+-
EWFCT
16: RSNF
KADR+-
17:
STARTF
KDATA~
F2 (task-specific):
0
4,16
7
11
12 13
14
CPU
KSEC,KWD EfHER
DWT
CURT DHT
DVT
10:
BUSODD INIT EODFCT
DDR+- XPREG+- EVENFIELD EVENFIELD
11: MAGIC RWC EOSFCT
CSR+-
SEIMODE
12:
DNS+-
RECNO
ERBFCT
13:
ACDEST
XFRDAT EEFCT
14:
IR~
SWRNRDY EBFCT
15:
IDISP
NFER
ECBFCT
16:
ACSOURCE STROBON EISFCT
17:
-
67
RAM
Related
(SWMODE)
WRTRAM
RDRAM
SRB+-
RAM
Related

Xerox Alto I Specifications

General

Brand	Xerox
Model	Alto I
Category	Desktop
Language	English