| Words | Bits | Function |
| SR 232 - SR 235 | 00 - 15 | Input area for macro functions. Contains input operands for MCRO(99) (may be used for working bits, when MCRO(99) is not used) |
| SR 236 - SR 239 | 00 - 15 | Output area for macro functions. Contains output operands for MCRO(99) (may be used for working bits, when MCRO(99) is not used) |
| SR 240 | 00 - 15 | Contains set value SV, when input interrupt 0 is used in counter mode (4 hexadecimal digits) (may be used for working bits, when input interrupt 0 is not used in counter mode) |
| SR 241 | 00 - 15 | Contains set value SV, when input interrupt 1 is used in counter mode (4 hexadecimal digits) (may be used for working bits, when input interrupt 1 is not used in counter mode) |
| SR 242 | 00 - 15 | Contains set value SV, when input interrupt 2 is used in counter mode (4 hexadecimal digits) (may be used for working bits, when input interrupt 2 is not used in counter mode) |
| SR 243 | 00 - 15 | Contains set value SV, when input interrupt 3 is used in counter mode (4 hexadecimal digits) (may be used for working bits, when input interrupt 3 is not used in counter mode) |
| SR 244 | 00 - 15 | Contains current value (PV-1), when input interrupt 0 is used in counter mode (4 hexadecimal digits) |
| SR 245 | 00 - 15 | Contains current value (PV-1), when input interrupt 1 is used in counter mode (4 hexadecimal digits) |
| SR 246 | 00 - 15 | Contains current value (PV-1), when input interrupt 2 is used in counter mode (4 hexadecimal digits) |
| SR 247 | 00 - 15 | Contains current value (PV-1), when input interrupt 3 is used in counter mode (4 hexadecimal digits) |
| SR 248, SR 249 | 00 - 15 | Contains current value PV of the high-speed counter (may be used for working bits, when high-speed counter is not used) |
| SR 250 | 00 - 15 | Analog setting of value 0. Keeps 4 digit BCD value (0000 - 0200) set via analog potentiometer on the PLC controller casing. |
| SR 251 | 00 - 15 | Analog setting of value 1. Keeps 4 digit BCD value (0000 - 0200) set via analog potentiometer on the PLC controller casing. |
| SR 252 | 00 | Reset of the high-speed counter |
| 01 - 07 | Not used | |
| 08 | Peripheral port. Switches on for the reset of the peripheral port (this doesn't apply to a case when peripheral device is connected). Bit automatically changes state to OFF after the reset | |
| 09 | Not used | |
| 10 | PLC Setup Reset Bit. When on, it initializes PC setup (DM6600-DM6655). It automatically goes to OFF after the reset. This applies only if the PC is in PROGRAM mode | |
| 11 | Forced Status Hold Bit. OFF: bits used in the operation of forced set/reset are cleared when changing from PROGRAM to MONITOR mode. ON: bits used in the operation of forced set/reset keep their states when changing from PROGRAM to MONITOR mode. | |
| 12 | I/O Hold bit. OFF: IR and LR bits are reset when starting or ending an operation. ON: IR and LR bits keep their states when starting or ending an operation. | |
| 13 | Not used | |
| 14 | Error Log Reset Bit. Bit state OFF clears the record of error taking place. Bit automatically goes off after the operation | |
| 15 | Not used | |
| SR 253 | 00 - 07 | FAL error code. Location contains error code (2 digit number). FAL number is stored at this location upon executing FAL(06) or FAL(07) instructions. Location contents are reset upon executing FAL 00 instruction or by clearing an error from peripheral device |
| 08 | Not used | |
| 09 | Cycle Time Overrun Flag. Bit goes to ON when program length doesn't allow cycle of input/output scanning to be executed in a specified time period | |
| 10 - 12 | Not used | |
| 13 | Flag always on | |
| 14 | Flag always off | |
| 15 | First Cycle Flag. Goes ON during the first cycle at the beginning of the operation | |
| SR 254 | 00 | 1 min clock impulse (30s on, 30s off) |
| 01 | 0.02s clock impulse (0.01s on, 0.01s off) | |
| 02 | Negative (N) flag | |
| 03 - 05 | Not used | |
| 06 | Differential Monitor Flag | |
| 07 | STEP(8) execution flag | |
| 08 - 15 | Not used | |
| SR 255 | 00 | 0.1s clock impulse (0.05s on, 0.05s off) |
| 01 | 0.2s clock impulse (0.1s on, 0.1s off) | |
| 02 | 1.0s clock impulse (0.5s on, 0.5s off) | |
| 03 | Instruction Execution Error (ER) Flag. Changes state to ON if error occurs during instruction execution | |
| 04 | Carry (CY) flag | |
| 05 | "Greater than" (GR) flag | |
| 06 | "Equals" (EQ) flag | |
| 07 | "Less than" (LE) flag | |
| 08 - 15 | Not used |
