Appendix C
Memory Areas
578
AR Area
These bits mainly serve as flags related to CPM2A/CPM2C operation. These bits retain their status even after the
CPM2A/CPM2C power supply has been turned off or when operation begins or stops.
Word(s)
Bit(s)
Function
Page
AR 00,
AR 01
00 to 15
Not used.
AR 02
00
Expansion Unit Error Flag for 1st Unit
These flags turn ON
h
h
i
i
---
01
Expansion Unit Error Flag for 2nd Unit
g
when there is an error in
the corresponding Unit
02
Expansion Unit Error Flag for 3rd Unit
the corresponding Unit.
03
Expansion Unit Error Flag for 4th Unit
(Not used by CPM2A.)
04
Expansion Unit Error Flag for 5th Unit
(Not used by CPM2A.)
05 to 07
Not used.
08 to 11
Number of Expansion Units and Expansion I/O Units Connected
---
12 to 15
Not used.
AR 03 to
AR 06
00 to 15
Not used.
AR 07
00 to 11
Not used.
---
12
Valid only for CPM2C CPU Units with lot numbers of 0190O or later. (Cannot be used
for CPM2C CPU Units with lot numbers of 3180O or earlier and cannot be used with
CPM2A CPU Units.) Refer to
1-3 Changes in SW2
for information on lot numbers.
ON:
SW2 on the front of the CPU Unit is ON.
OFF: SW2 on the front of the CPU Unit is OFF.
13 to 15
Not used.
AR 08
00 to 03
RS-232C Port Error Code
0: Normal completion
1: Parity error
2: Frame error
3: Overrun error
250,
258
04
RS-232C Communications Error Flag
Turns ON when an RS-232C port communications error occurs.
05
RS-232C Transmit Ready Flag
Turns ON when the PC is ready to transmit data. (No-protocol and Host Link only)
06
RS-232C Reception Completed Flag
Turns ON when the PC has completed reading data. (No-protocol only)
07
RS-232C Reception Overflow Flag
Turns ON when an overflow has occurred. (No-protocol only)
08 to 11
Peripheral Port Error Code
0: Normal completion
1: Parity error
2: Frame error
3: Overrun error
12
Peripheral Port Communications Error Flag
Turns ON when a peripheral port communications error occurs.
13
Peripheral Port Transmit Ready Flag
Turns ON when the PC is ready to transmit data. (No-protocol and Host Link only)
14
Peripheral Port Reception Completed Flag
Turns ON when the PC has completed reading data. (No-protocol only)
15
Peripheral Port Reception Overflow Flag
Turns ON when an overflow has occurred. (No-protocol only)
AR 09
00 to 15
RS-232C Port Reception Counter
(4 digits BCD)
Valid only when no-protocol communications are used.
258
AR 10
00 to 15
Peripheral Port Reception Counter
(4 digits BCD)
Valid only when no-protocol communications are used.
258