| C4 | C4A | 705C4A | C8 | C8A | 705C8 | 705C8A | C12 | C12A | C9 | C9A | 705C9 | 705C9A | |
| USER ROM | 4160 | 4160 | - | 7744 | 7744 | - | - | 12,096 | 12,096 | 15,760-15,936 | 15,760-15,936 | - | - |
| USER EPROM | - | - | 4160 | - | - | 7596-7740 | 7596-7740 | - | - | - | - | 15,760-15,936 | 12,096-15,936 |
| CODE SECURITY | NO | YES | YES | NO | YES | YES | YES | NO | YES | NO | YES | NO | YES |
| RAM | 176 | 176 | 176 | 176 | 176 | 176-304 | 176-304 | 176 | 176 | 176-352 | 176-352 | 176-352 | 176-352 |
| OPTION REGISTER (IRQ/RAM/ SEC) | NO | NO |
$1FDF (IRQ/SEC) | NO | NO |
$1FDF (IRQ/RAM/ SEC) |
$1FDF (IRQ/RAM/SEC) | NO | NO |
$3FDF (IRQ/RAM) |
$3FDF (IRQ/RAM) |
$3FDF (IRQ/RAM) |
$3FDF (IRQ/RAM) |
| MASK OPTION REGISTER(S) | NO | NO | $1FF0-1 | NO | NO | NO | $1FF0-1 | NO | NO | NO | NO | NO | $3FF0-1 |
| PORTB KEYSCAN (PULLUP/ INTERRUPT) | NO |
YES MASK OPTION |
YES MOR SELECT- ABLE | NO |
YES MASK OPTION | NO |
YES MOR SELECTABLE |
YES MASK OPTION |
YES MASK OPTION | NO |
YES MASK OPTION | NO |
YES MOR SELECTABLE |
| PC7 DRIVE | STANDARD |
HIGH CURRENT |
HIGH CURRENT | STANDARD |
HIGH CURRENT | STANDARD |
HIGH CURRENT |
HIGH CURRENT |
HIGH CURRENT | STANDARD |
HIGH CURRENT | STANDARD |
HIGH CURRENT |
| PORT D |
PD7, 5-0 INPUT ONLY |
PD7, 5-0 INPUT ONLY |
PD7, 5-0 INPUT ONLY |
PD7, 5-0 INPUT ONLY |
PD7, 5-0 INPUT ONLY |
PD7, 5-0 INPUT ONLY |
PD7, 5-0 INPUT ONLY |
PD7, 5-0 INPUT ONLY |
PD7, 5-0 INPUT ONLY |
PD7, 5-0 BIDIREC- TIONAL |
PD7, 5-0 BIDIRECTIONAL |
PD7, 5-0 BIDIRECTIONAL |
PD7, 5-0 BIDIRECTIONAL |
| COP | NO | YES | YES | NO | YES | YES | TWO TYPES | YES | YES | YES | YES | YES |
TWO TYPES |
| COP ENABLE | - | MASK OPTION | MOR | - |
MASK OPTION | SOFTWARE |
SOFTWARE + MOR |
MASK OPTION |
MASK OPTION | SOFTWARE | SOFTWARE | SOFTWARE |
SOFTWARE + MOR |
| COP TIMEOUT | - |
64 ms (@4 MHz osc) |
64 ms (@4 MHz osc) | - |
64 ms (@4 MHz osc) |
SOFTWARE SELECTABLE |
SOFTWARE + MOR SELECTABLE |
64 ms (@4 MHz osc) |
64 ms (@4MHz osc) |
SOFTWARE SELECTABLE |
SOFTWARE SELECTABLE |
SOFTWARE SELECTABLE |
SOFTWARE + MOR SELECTABLE |
| COP CLEAR | - | CLR $1FF0 | CLR $1FF0 | - | CLR $1FF0 |
WRITE $55/$AA TO $001D |
WRITE $55/$AA TO $001D OR CLR $1FF0 | CLR $3FF0 | CLR $3FF0 |
WRITE $55/$AA TO $001D |
WRITE $55/$AA TO $001D |
WRITE $55/$AA TO $001D |
WRITE $55/$AA TO $001D OR CLR $3FF0 |
| CLOCK MONITOR | NO | NO | NO | NO | NO | YES | YES | NO | NO | YES | YES | YES |
YES (C9A MODE) |
| ACTIVE RESET | NO | NO | NO | NO | NO |
COP/CLOCK MONITOR |
PROGRAM- MABLE COP/CLOCK MONITOR | NO | NO |
POR/COP/ CLOCK MONITOR |
POR/COP/ CLOCK MONITOR |
POR/COP/ CLOCK MONITOR |
POR/C9A COP/ CLOCK MONITOR |
| STOP DISABLE | NO |
MASK OPTION | NO | NO |
MASK OPTION | NO | NO |
MASK OPTION |
MASK OPTION | NO | NO | NO |
MOR SELECTABLE (C12A MODE) |
NOTES: