```c
// struct REGPACK reg;
reg.r_ax=0x1130;
reg.r_bx=reg_bx;
int86(0x10,®);
return MK_FP(reg.r_es,reg.r_bp);
```
// struct REGPACK reg;
reg.r_ax=0x1130;
reg.r_bx=reg_bx;
int86(0x10,®);
return MK_FP(reg.r_es,reg.r_bp);
```
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中国DOS联盟论坛 » DOS开发编程 & 发展交流 （开发室） » How to access the BP register?
View 1,868 Replies 3
Original Poster
Posted 2010-11-08 05:43 · 中国 广东 深圳 电信
Floor 2
Posted 2010-11-08 10:00 · 中国 广东 深圳 福田区 电信
```c
// Get the starting address of the 8x8 character set
unsigned char* GetCharacterPoint()
{
unsigned short wSeg = 0;
unsigned short wOff = 0;
__asm push es
__asm push bp
__asm mov ax, 1130H
__asm mov bh, 03H // Get the starting address of the 8x8 font
__asm int 10h
__asm mov ax, bp
__asm pop bp // Very important, otherwise the program will crash
__asm mov wOff, ax
__asm mov ax, es
__asm mov wSeg, ax
__asm pop es
return ((unsigned char *)(unsigned long)MK_FP(wSeg, wOff));
}
[ Last edited by firstsail on 2010-11-8 at 10:02 ]
```
// Get the starting address of the 8x8 character set
unsigned char* GetCharacterPoint()
{
unsigned short wSeg = 0;
unsigned short wOff = 0;
__asm push es
__asm push bp
__asm mov ax, 1130H
__asm mov bh, 03H // Get the starting address of the 8x8 font
__asm int 10h
__asm mov ax, bp
__asm pop bp // Very important, otherwise the program will crash
__asm mov wOff, ax
__asm mov ax, es
__asm mov wSeg, ax
__asm pop es
return ((unsigned char *)(unsigned long)MK_FP(wSeg, wOff));
}
[ Last edited by firstsail on 2010-11-8 at 10:02 ]
```
Floor 3
Posted 2010-11-08 15:23 · 中国 广东 电信
Uh, boss upstairs, I need C language, no inline assembly...
Floor 4
Posted 2010-11-26 08:21 · 中国 福建 厦门 电信
In C language, although you can declare register variables to use registers as much as possible for variables, bp is generally used to pass parameters. So even when using embedded assembly to use bp, you have to be very careful, otherwise the program is very easy to crash.
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