IORGE

Greetings, Stanislav! [Saturday September 9, 2000] at [21:31:04] Stanislav Udin wrote a letter to All. They discussed the topic "IORGE". Let's continue what we started... SU> Please give the scheme for creating the subject, implemented SU> only on microcircuits, without transistors. On one element from 555LP8: input - at +5V, output - at /IOGE, /OE - at device _address_ decoder (give it the A4 address if for a modem a la M.Kondratiev). For the device decoder itself, you need to take a “clean” /IORQ with 20 Z80 legs. =============== here we will start the file "MakeIOGE.C" ================ . . . The diagram shows quite clearly how to connect modification to the computer. You may need to do blocking all input/output ports on your computer, including moment when the KP580BB55A ports are being accessed, to exclude conflicts! The control signal for this can be log."0" on the 6th pin (/CS) of BB55A. For example, for Scorpion you can do this: (I haven’t tried it in practice, but it should work) - Remove the /IORQ signal for the circuit from the 20th leg of the Z80. o+5B │ 1K B│<┘E On the 6th pin.>──o──███─o─┤ KT361, KT3107, etc. KP580BB55A │ │ │ K └──┤├──┘ │* 20pF └───> per signal /IORQCE * The capacitor may not be installed. Or use a more “cool” scheme, for the implementation of which you will need a free element MC K555LP8: 1/4 K555LP8 ┌──┬──┐ +5B o─2┤D0│1 ├3───> to the /IORQCE signal ├──┤ │ On the 6th pin>─1oE0│ │ KP580BB55A └──┴──┘ . . . ============== here we will end the file "MakeIOGE.C" ================ Best regards, Felix. [I.ZX] 27