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3-6-2 Special I/O Unit Data
Special I/O Units are allocated 1000 or 1600 words in the DM Area depending on
the value set in word DM 6602 of the PC Setup. The DM 6602 setting determines
whether the Special I/O Unit Data area is setup for 10 or 16 Units and whether
the data is stored in read/write DM (DM 1000 to DM 2599) or read-only DM
(DM 7000 to DM 8599). Refer to Appendix E for details.
Unit Addresses
0DM 1000 to DM 1099 or DM 7000 to DM 7099
1DM 1100 to DM 1199 or DM 7100 to DM 7199
2DM 1200 to DM 1299 or DM 7200 to DM 7299
3DM 1300 to DM 1399 or DM 7300 to DM 7399
4DM 1400 to DM 1499 or DM 7400 to DM 7499
5DM 1500 to DM 1599 or DM 7500 to DM 7599
6DM 1600 to DM 1699 or DM 7600 to DM 7699
7DM 1700 to DM 1799 or DM 7700 to DM 7799
8DM 1800 to DM 1899 or DM 7800 to DM 7899
9DM 1900 to DM 1999 or DM 7900 to DM 7999
ADM 2000 to DM 2099 or DM 8000 to DM 8099
BDM 2100 to DM 2199 or DM 8100 to DM 8199
CDM 2200 to DM 2299 or DM 8200 to DM 8299
DDM 2300 to DM 2399 or DM 8300 to DM 8399
EDM 2400 to DM 2499 or DM 8400 to DM 8499
FDM 2500 to DM 2599 or DM 8500 to DM 8599
Note These DM words can be used for other purposes when not allocated to Special
I/O Units.
3-6-3 Error History Area
DM 6000 to DM 6030 are used to store up to 10 records that show the nature,
time, and date of errors that have occurred in the PC.
The Error History Area will store system-generated or FAL(06)/FALS(07)-gener-
ated error codes whenever AR 0715 (Error History Enable Bit) is ON. Refer to
Section 9 Troubleshooting for details on error codes.
Area Structure Error records occupy three words each stored between DM 6001 and DM 6030.
The last record that was stored can be obtained via the content of DM 6000 (Er-
ror Record Pointer). The record number, DM words, and pointer value for each of
the ten records are as follows:
Record Addresses Pointer value
None N.A. 0000
1DM 6001 to DM 6003 0001
2DM 6004 to DM 6006 0002
3DM 6007 to DM 6009 0003
4DM 6010 to DM 6012 0004
5DM 6013 to DM 6015 0005
6DM 6016 to DM 6018 0006
7DM 6019 to DM 6021 0007
8DM 6022 to DM 6024 0008
9DM 6025 to DM 6027 0009
10 DM 6028 to DM 6030 000A
DM (Data Memory) Area Section 3-6