Chapter 17 (Expert MS-DOS Programming) –
Assessment
True-False
Please indicate whether each statement is True (T) or False (F).
1. In large model programs, all code segments have the same name.
2. The following are all permissible segment ALIGN types: BYTE, WORD, DWORD, REAL4.
3. Only one code segment may be created in a single program module.
4. The segment combine type tells the linker how to combine segments having the same name.
5. The CLASS type in a segment definition makes it possible to combine two segments having
different names.
6. The following is an example of a valid segment override:
mov eax,ds:var1
7. All COM programs use the small memory model.
8. The ASSUME directive permits the assembler to calculate the offsets of labels and variables.
9. When a key is pressed on the keyboard, the Intel 8259 programmable interrupt controller signals
the CPU to suspend execution of the current program.
10. An EXE program can have overlapping code, data, and stack segments.
11. When an interrupt executes, an address in the Exception Process Table is used to locate the
interrrupt handler.
12. Memory-mapped video is set up so that when characters are placed in memory at predetermined
addresses, the characters appear on the video display only when a special control value is output to
a hardware port.
13. IA-32 systems offer two types of hardware input-output: memory-mapped, and port-based.
14. Port-based I/O uses the IN and OUT instructions to read and write data to specific numbered
locations.
15. The Speaker Demo Program uses the IN instruction to turn the speaker on.