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--- Extended BIOS of Libretto20-100 --------------------------------
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Information in this document was obtained by analyzing Libretto20
by Mr. M. Iizuka (PXN02133@niftyserve.or.jp) individually. So some
mistakes may be contained in this document. Please use with care.
If you want to redistribute this document, please attach the
information on the source of this document.

* The data from 50CT and 100CT were added by Y. Shimazaki
  (yamatori@ab11.yamanashi.ac.jp). Those data were marked with `#'.

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*** TOSHIBA Libretto 20, 50, 60, 70, 100 Extended BIOS Call Function ***

----------1544F0-----------------------------
INT 15 - BIOS Support Check
        AX = 44f0h
Return: CFLAG = 00h function successful

----------1544F1-----------------------------
INT 15 - BIOS Open Interface
        AX = 44f1h
Return: CFLAG = 00h function successful

----------1544F2-----------------------------
INT 15 - BIOS Close Interface
        AX = 44f2h
Return: CFLAG = 00h function successful

----------1544F3-----------------------------
INT 15 - BIOS Status Get
        AX = 44f3h
        BX = mode (*1)
Return: CFLAG = 00h function successful
        CX = status (*2)
----------1544F4-----------------------------
INT 15 - BIOS Status Set
        AX = 44f4h
        BX = mode (*1)
        CX = status (*2)
Return: CFLAG = 00h function successful

---------------------------------------------(*1)
Format of mode (BX Register) information:

Mode	Description		Need to reboot? (#)
0100h   Power-up Mode			No
0108h	CPU Cache Policy (#)		Yes
010ah   System Beep On/Off		No
010bh   Battery Alarm On/Off		No
010ch   Panel Alarm On/Off		No
010dh   Panel Power On/Off		No
010fh   Alarm Power On			No
0110h   System Auto Off			No
011dh	Boot Device (#)			Yes
011fh	CPU Cache Policy (#)		Yes
0125h   Standby Time			No
012dh	Hibernation/Suspend (#)		No
0305h   LCD Back Light Power		No
0308h	Display Stretch (#)		No
0501h	Parallel Port (#)		Yes
0505h	Pointing Device (#)		Yes
0508h	Infrared Port (#)		No

---------------------------------------------(*2)
Format of status (CX Register) information:

Mode    Description
0100h   0000h Boot
        0001h Hibernation (/Suspend for 100)

0108h	0108h 011fh policy	# Checked with 100CT only
  &	  1     0    W/B
011fh     1     1    W/T
	  0     1    Disable

010ah   0000h Off
        0001h On

010bh   0000h Off
        0001h On

010ch   0000h Off
        0001h On

010dh   0000h Disabled
        0001h Enabled

010fh   bit    0: Enable/Disable Switch
                  0h Enabled
                  1h Disabled
        bit 1- 6: min
        bit 7-15: hour

0110h   0001h Disabled
        0020h 10min
        0080h 20min
        0200h 30min
        0800h 40min
        2000h 50min
        8000h 60min

011dh	0000h FD->HD
	0001h HD->FD

011fh	see 0108h

0125h   0001h  0min
        0010h  5min
        0020h 10min
        0040h 15min
        0200h 30min
        1000h 45min
        8000h 60min

012dh	0000h suspend		# reported by Mr. Nomura, for 100 only
	0001h hibernation

0305h   0000h low
        0001h  |
        0002h  |
        0003h high

0308h	0000h Normal
	0001h Stretch

0501h	0010h ECP		# 0020h is uni-directional for 20/30?
	0040h Bi-Directional

0505h	0000h Internal/External Auto Select
	0001h Simultaneous

0508h	0001h IrDA 1.0		# Not supported by 100CT
	0002h ASK (Sharp's proprietary mode)

---------------------------------------------(*3)
BIOS Status Get/Set Process:

1. BIOS Open Interface Function Call
2. BIOS Status Get/Set Function Call
3. BIOS Close Interface Function Call

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