Octagon XE-900, Справочное руководство

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87
User switches
The user switches are positions 4 and 5 and are associated with GPI 2 (user switch
1) and GPI 23 (user switch 2.) The INT17 functions provide an easy method to
implement software routines according to whether or not a switch is On. Refer to
the INT17 calls to read user switch on page 87.
INT17 calls to read user switches
The INT17 functions provide an easy method to implement software routines
according to whether or not a user switch is On.
Function: 0fbh
Sub-Function: 0bh
Purpose: To read user jumper
Calling Registers:
AH 0fbh
AL 0bh
DX 0ffffh
Return Registers:
Carry flag cleared if successful
AL Jumper data
bit 0 user jumper 1. 1=on, 0=off
bit 1 user jumper 2. 1=on, 0=off
Carry flag set if error
AL Error code
Comments: This function shall be used to read the user
switches
Programming example:
/* Inline assembly code for Borland C++ 3.1 */
unsigned char aData;
asm {
MOV AX, 0fb0bh
MOV DX, 0ffffh
INT 17h
MOV aData, AL
}
if (aData & 1)
printf(“U1 switch is ON\n”);
BIOS programming using REFLASH.EXE
The BIOS on the XE–900 SBC can be updated using the REFLASH.EXE utility.
This utility can be found in the \XE900\EXTBIOS subdirectory of the utilities (see
page 118 to download utilities). To update the BIOS the following steps must be
taken:
1. Copy REFLASH.EXE, REFLASH.CMD, and BIOS.ROM from the
\XE900\EXTBIOS subdirectory to the root of a bootable CompactFlash disk.
2. Boot the XE–900 SBC from the CompactFlash disk with a CRT monitor or flat
panel connected to the system.