Parent 
NOTE:   This web site is not some kind of 'official' documentation hub for the XT-IDE card.
It is simply the result of someone who decided to add to the documentation that exists elsewhere.



VCF XT-IDE  Rev 2


This is the second revision of the XT-IDE card produced by members of the Vintage Computer Federation Forums (VCFF),  not the first nor third nor fourth revisions.


XT-IDE basics

Before reading further, read the web page at here, to gain information on the basics of the XT-IDE.


Photo / Identification

Printed on the card is "XT-IDE, REV 02  WWW.VINTAGE-COMPUTER.COM".

A photo of an XT-IDE Rev 2 card that does not have the optional serial port ('UART') installed, is at here.
A photo of an XT-IDE Rev 2 card with the optional serial port ('UART') installed, is at here.


Main article

See the wiki styled information here at the VCF.


Changes from Rev 1

• 'Hi-speed' mode (a.k.a. 'Chuck mod') added.  See here.
• Optional provision of +5V to pin 20 on the IDE connector.  A jumper (P9) controls this.  For those CF-to-IDE adapters and DOMs that support this.
• If desired, a 28C256 type BIOS ROM (boot ROM) can be used instead of a 28C64 type.  Additional information below.
• OPTIONAL FITMENT: Serial port for accessing a serial drive.
• OPTIONAL FITMENT: Molex power connector.  This is a power outlet.  If desired, run a lead from here to power your IDE device.


XTIDE Universal BIOS (XUB) - Versioning

The page at here will give you an idea of how the versioning of the XUB has changed through the years.

Within this web page, my convention is:
• 1.x.x means versions 1.1.0 through to 1.1.5
• 2.x.x means any version that displays its version on-screen as "v2.0.0"  (example: "v2.0.0β3+ (2019-02-14)")
• Rxxx means any version that displays its version on-screen as a three digit number preceeded by an R  (example: "r624 (2022-10-02)")

( Confusing the matter, most 2.x.x were often referred to by an 'R' number, but that number was not displayed on-screen. )


XTIDE Universal BIOS (XUB) - 'Device type' setting

When using XTIDECFG.COM to configure a freshly downloaded 2.x.x/Rxxx version of the XTIDE Universal BIOS for this card, you will need to alter the 'Device type' setting - see here for a screenshot.

What you set that to depends on:
• Whether your VCF XT-IDE card is jumpered for 'Hi-speed' mode or 'Compatibility' mode.
• Whether or not your VCF XT-IDE card is in an Olivetti M24 / AT&T PC6300 / Xerox 6060 / Logabax Persona 1600.

To establish the setting you need, refer to the table in the section that follows.


Hi-Speed mode versus Compatibility mode

• It is expected (only for performance reasons) that the Rev 2 card be jumpered for hi-speed mode, and using a 2.x.x/Rxxx version of the XTIDE Universal BIOS (per option #1 in the table below).

• Compatiblity mode changes the IDE interface (specifically, its register map) to how it is on an XT-IDE Rev 1 card.  You will need to jumper your Rev 2 card for this mode if you choose to use a 1.x.x version of the XTIDE Universal BIOS.

• The four options for the Rev 2 card are show in the following table:

  Version of
XTIDE Universal BIOS
on Rev 2 card		 Jumper setting
of mode
on Rev 2 card		 Configure 'device type' setting
in XTIDE Universal BIOS
version 2.x.x/Rxxx for		    Comments
Option #1 2.x.x or Rxxx Hi-speed "XTIDE rev2 or modded rev1"   1. Best performing option.   2. Does not work in an Olivetti M24 or AT&T PC6300 or Xerox 6060 or Logabax Persona 1600.
Option #2 2.x.x or Rxxx Hi-speed "XTIDE rev2 (Olivetti M24)"   Only for Olivetti M24 / AT&T PC6300 / Xerox 6060 / Logabax Persona 1600.   Early 2.x.x versions of XUB lack this device type.
Option #3 2.x.x or Rxxx Compatibility "XTIDE rev1"  
Option #4 1.x.x Compatibility [ not applicable ]  



BIOS ROM (EEPROM) size

Either a 28C64 or 28C256 EEPROM can be used.  Set the four BIOS ROM type jumpers (K1/K2/K6/K7) accordingly, per the diagram at here.

Assuming that a base address of D0000 (the default) has been configured via the card's jumpers, the motherboard address space used by the BIOS ROM is:
28C64 (8 KB sized):   Address space = D0000 to D1FFF
28C256 (32 KB sized):   Address space = D0000 to D7FFF


I/O port range used by the IDE interface

Via switches/jumpers on the card, if you change the base I/O address of the IDE interface from the default of 300 (hex), then you will need to reflect that change within the XTIDE Universal BIOS (XUB) within the EEPROM (so that the XTIDE Universal BIOS knows which I/O addresses to use).

>>> RECONFIGURATION OF XUB VERSIONS 1.x.x

For 1.x.x versions of the XTIDE Universal BIOS (XUB), you use IDECFG.COM to reconfigure the XUB (read existing configuration, make change, write new configuration).
For example, the base I/O address area of IDECFG.COM for version 1.1.5 of the XTIDE Universal BIOS is shown at here.
The IDECFG.COM program is not generic - to play safe, use the IDECFG.COM that is supplied with the particular XUB version that you are using (it is tailored for that version of XUB).

>>> RECONFIGURATION OF XUB VERSIONS 2.x.x AND Rxxx

For 2.x.x/Rxxx versions of the XTIDE Universal BIOS (XUB), you use XTIDECFG.COM to reconfigure the XUB (read existing configuration, make change, write new configuration).
For example, the base I/O address area of XTIDECFG.COM for version '2.0.0 Beta 3+ R622' of the XTIDE Universal BIOS is shown at here.
The XTIDECFG.COM program is not generic - to play safe, use the XTIDECFG.COM that is supplied with the particular XUB version that you are using (it is tailored for that version of XUB).


Switch/jumper settings

A diagram for the IDE functionality is at here     ('IDE interface')
A diagram for the ROM functionality is at here
A diagram for the optional UART functionality is at here

Via switches/jumpers on the card, if you change the base I/O address of the IDE interface from the default of 300 (hex), then you will need to reflect that change within the XTIDE Universal BIOS (XUB) within the EEPROM (so that the XTIDE Universal BIOS knows which I/O addresses to use) - see the 'I/O port range used by the IDE interface' section above.


Optional serial port  (optional 'UART')

Intended for accessing a serial drive.

P14 on the card is where a header-to-DE9 cable/adapter is connected to.  See here for details.

With two exceptions, the serial port is a 'normal' serial port:
  1. The first exception is that the port operates 4 times faster than normal.  For example, if you ran some terminal emulation software, then within that software, set the port speed to 1200 baud, the port would actually operate at 4800 baud.   BTW: The 4 x speed comes about because the XT-IDE rev 2 card uses a 7.3728 MHz crystal, rather than a standard 1.8432 one.
  2. The second exception is that only two hardware handshaking (a form of flow control) lines are implemented: RTS and CTS.  The DTR, DSR, RI and DCD lines are not implemented.

Some information about using the Rev 2 card to access a serial drive is at here.

Note that in May 2019, a bug was fixed in SERDRIVE.EXE  The bug prevented the use of 3.5" 720K images.  See posts 423 and 424 at here.


Problems

See here


Other

Circuit diagram

Connector P14

Kicad images   (8 pages)

Power connector - Jameco part 117568   (2 pages)