VCF XT-IDE Rev 1
This page is about the first revision of the XT-IDE card produced by the Vintage Computer Forums (VCF), not the later second nor third nor fourth revisions.
Production started in about 2009, and ended about 2012 when the second revision of the card was designed.
This revision of the card is typically referred to as 'XT-IDE Rev 1' or 'XT-IDE Revision 1' in order to distinguish it from later revisions of the card.
Photo / Identification
A photo of an XT-IDE Rev 1 card is here.
Printed on the card (left of the IDE connector) is "XT-IDE, REV 01".
Before reading further, read the web page at here, to gain information on the basics of the XT-IDE.
A diagram is at here
The setting of jumper K1 is only relevant if you use the drive selection methodology of 'cable select' rather than the normally used methodology of master/slave.
Circuit diagram / Component list
In the component list, note the recommendation (or requirement?) for the Amtel brand of 28C64 EEPROM chip. My further recommendation is that you use the 'B' verson of that chip, the AT28C64B instead of the AT28C64, because of problems I have seen using XTIDECFG.COM to program the AT28C64.
XTIDE Universal BIOS
Although later versions exist, version 1.1.4 and 1.1.5 are typical for XT-IDE Rev 1 cards.
Version 1.1.5 can be downloaded from here.
If you chose to use a later version (2.x.x) in the XT-IDE Rev 1, set the configuration option of 'device type' to 'XTIDE rev 1'.
Reprogramming the 28C64 EEPROM
A DOS program named XTIDECFG.COM was provided to do this.
Typical operation #1 - Programming XTIDE Universal BIOS into empty 28C64 EEPROM
1. Fit 28C64 EEPROM into card.
2. Ensure that jumpers JP1 and JP2 are both on.
3. Obtain BIN file of XTIDE Universal BIOS, e.g. IDE_XT.BIN
4. Run XTIDECFG.COM - a menu is presented.
5. XTIDECFG.COM: Read in the IDE_XT.BIN file.
6. XTIDECFG.COM: Make any required configuration changes.
7. XTIDECFG.COM: Write the configuration to the EEPROM. See note 1 below.
Typical operation #2 - Configuration change
1. Ensure that jumpers JP1 and JP2 are both on.
2. Run XTIDECFG.COM - a menu is presented.
3. XTIDECFG.COM: Choose to read the current contents of the EEPROM.
4. XTIDECFG.COM: Make any required configuration changes (e.g. set new base address of the I/O range).
5. XTIDECFG.COM: Write the changed configuration back to the EEPROM. See note 1 below.
NOTE 1: There is a 'SDP command' option. Photo here. Disable that option if your EEPROM is the base version of the AT28C64. Enable it if your EEPROM is the 'B' version, the AT28C64B.
After the XT-IDE cards, of both Rev 1 and Rev 2, were produced, it was discovered that resistor R6 should be instead a link (Rev 2 photo). This defect is only of concern if you use the drive selection methodology of 'cable select' rather than the normally used methodology of master/slave.
Boot lockup due to damaged/misconfigured XTIDE Universal BIOS
Sometimes, a user may discover that their once booting computer (containing an XT-IDE card) now locks up during boot, and that the computer boots if the XT-IDE card is removed.
One known cause (of a few) is that, for whatever reason, the XTIDE Universal BIOS software within the EEPROM chip has become damaged/corrupt/improper. If that is the case, then the XTIDE Universal BIOS needs to be reloaded (or possibly just reconfigured).
But a catch-22 situation exists, because to load/reconfigure the XTIDE Universal BIOS using XTIDECFG.COM, the XT-IDE card needs to be present and the computer needs to boot.
One answer is to:
1. Remove jumper JP1 from the XT-IDE card. That action disables the EEPROM.
2. Put the XT-IDE card in the computer.
3. Power on the computer, booting from a floppy that contains XTIDECFG.COM
4. When the DOS prompt appears, put jumper JP1 back on.
5. Run XTIDECFG.COM
MODIFICATION: IDE pin 20
Normally, for use with the XT-IDE rev 1 card, CF-to-IDE adapters and DOMs have to be externally powered, such as shown in the photo at here.
But some (repeat: some) can be optionally powered via pin 20 of the IDE interface connector. On the XT-IDE Rev 1 card, pin 20 of the connector (P1) is not connected to anything. So, what some owners of XT-IDE Rev 1 cards did, was to solder on a wire that connected pin 20 of the IDE connector to +5 volts. A photo of that modification is here.
An example of a CF-to-IDE adapter that can be powered via pin 20 is pictured at here. One that cannot is pictured at here.
[ By the way. This modification was incorporated into revision 2 of the XT-IDE card (enabled/disabled via jumper P9). ]
MODIFICATION: The 'Chuck mod'
Be aware that some XT-IDE Rev 1 cards were modified by their owner to incorporate what became known as the 'Chuck mod', and later, 'hi-speed'. The modification made the card perform faster. The modification involved changing the card's wiring, and using a specially hacked 1.x.x version of the XTIDE Universal BIOS.
This means is that, in effect, there are two versions of the XT-IDE Rev 1 cards in existance.
It is important to realise that this modification has both hardware and software components.
[ By the way. This modification was incorporated into revision 2 of the XT-IDE card (named 'hi-speed' mode) and into 2.x.x versions of the XTIDE Universal BIOS. ]
Coexistence with MFM hard drive controller card
The XT-IDE Rev 1 card can coexist with an XT-class MFM hard drive controller card.
A photo of such a hardware configuration is at here. As shown here, when I power up the computer, the XTIDE Universal BIOS gives me the choice of hard drive booting from either the ST-225 drive (the "Foreign Hard Disk") or the CF card (the "SanDisk SDCFB-32"). I then use the up/down arrow keys on the keypad to select what I want to boot from, then press the ENTER key.
Make sure that the MFM drive is successfully booting before you add the XT-IDE card.