|
| Interrups | Categories | Contents |
Desc: Automatically asserted by the UART when COM1 needs attention, if the UART has been programmed to generate interrupts
BUG: This vector is modified but not restored by Direct Access v4.0, and may be left dangling by other programs written with the same version of compiled BASIC
Notes: On many PC's, COM3 shares this interrupt. May be masked by setting bit 4 on I/O port 21h. DOS 3.3+ revectors IRQ4 to a stack-switching routine unless STACKS=0 has been set in CONFIG.SYS. MS/PC-DOS use the IBM Interrupt Sharing Protocol (see #02568) when hooking this IRQ
See Also: INT 0B"COM2" - INT 54"DESQview" - INT 5C"DoubleDOS" - INT 7C"GO32"
Category: Hardware - Int 0Ch - I
|
| Interrups | Categories | Contents |