Data objects are the variables and constants you declare in your C programs. C51 generates a separate segment for each memory type for which a variable is declared. The following table lists the segment names generated for different variable data objects.
| Segment Name |
Description |
| ?CO?module_name |
Constants (strings and initialized variables) |
| ?XD?module_name |
Objects declared in xdata |
| ?DT?module_name |
Objects declared in data |
| ?ID?module_name |
Objects declared in idata |
| ?BI?module_name |
bit objects |
| ?BA?module_name |
Bit-addressable data objects |
| ?PD?module_name |
Objects declared in pdata |