– 6 –
MEMORY MAP
Hex Address
C000 - FFFF
16K ROM (only 8K used)
9000 - BFFF
16K I/O Slot (Keyboard and VDG control)
4000 - 8FFF
16K RAM (4K - 20K used)
0100 - 3FFF
Not Used
0080 - 00FF
RAM internal to the 6803
0015 - 007F
Not Used
0014
RAM Control Register
0013
Not Used
0012
Not Used
0011
Not Used
0010
Not Used
000F
Port 3 Control and Status Register
000E
Input Capture Register (low byte)
000D
Input Capture Register (high byte)
000C
Output Compare Register (low byte)
000B
Output Compare Register (high byte)
000A
Counter (low byte)
0009
Counter (high byte)
0008
Timer Control and Status Register
0007
Not Used
0006
Not Used
0005
Not Used
0004
Not Used
0003
Miscellaneous I/O Data Register
0002
Keyboard Output Lines
0001
Data Direction Register for miscellaneous I/O
0000
Data Direction Register for keyboard lines
Содержание TRS-80
Страница 3: ...3 SECTION I SYSTEM DESCRIPTION...
Страница 5: ...5 SYSTEM BLOCK DIAGRAM...
Страница 7: ...7 SECTION II SPECIFICATIONS...
Страница 9: ...9 SECTION III DISASSEMBLY REASSEMBLY...
Страница 11: ...11 SECTION IV THEORY OF OPERATION...
Страница 21: ...21 SECTION V TROUBLESHOOTING...
Страница 25: ...25 SECTION VI PARTS LIST...
Страница 30: ...30 SECTION VII PRINTED CIRCUIT BOARDS...
Страница 31: ...31 MAIN P C B TOP VIEW...
Страница 32: ...32 BOTTOM VIEW...
Страница 33: ...33 SECTION VIII IC INTERNAL CONNECTIONS...
Страница 34: ...34 IC INTERNAL CONNECTIONS U1 MC6803G Motorola or HD6803P Hitachi...
Страница 35: ...35 U11 MC6847P Motorola...
Страница 36: ...36 U2 SN74LS373N Motorola or MB74LS373M Fujitsu U7 SN74LS245N Motorola or MB74LS245M Fujitsu...
Страница 37: ...37 U3 MB8364M Fujitsu U9 10 PD4016C 1 NEC or PD4016D 1 NEC or MB8128 15P Fujitsu or MSM2128 20RS Oki...
Страница 41: ...41 U15 LM339N Motorola or PC339C NEC U18 SN74LS74AN Motorola or MB74LS74AM Fujitsu or HD74LS74AP Hitachi...
Страница 42: ...42 U16 MC1741CP1 Motorola or HA17741PS Hitachi U17 MC7805CT Motorola or NJM7805A JRC or PC7805H NEC...
Страница 43: ...43 SECTION IX SCHEMATlC DlAGRAM SECTION X EXPLODED VlEW...