After looking over the data transfer sequences, this device is not suited for EPP transfers. It is just too slow, and the handshaking is not EPP compliant.
It is well suited for standard parallel port bi-directional mode transfers, but will require your control program to to be structured properly to administer it.
To answer some of your questions:
1. I have had some considerable experience in this area and can tell you selecting a Bios settig of ECP only can cause some trouble. Although you can set the ECR mode bits to any supported state, you may find that it does not operate in the selected state on all machines. If you have a Bios setting of ECP+EPP or Normal, use that instead. I find the ECP+EPP works well on almost any machine that supports this selection.
2. You are correct that bit 5 of the control register is the data port directional control bit. Make sure your program sets it to the correct state on the initial entry.
3. The wiring setup does not support interrupt detection, so your control program will need to constantly read the status register bits 0-1 to detect the transfer request singal from device to host, and transfer ACK signal from device to host.
Depending on the Operating system of your PC, and what you use to write your control program, you may need to download some free program modules to get direct access to the PC printer port hardware addresses. One I use is called InPout32.dll Do a google search for the location of the downloads. The latest version works on both Win95-ME or NT/2000/XP based OS's.
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