From 99d1362915e0a7b83c03f55d9d48553b051445b6 Mon Sep 17 00:00:00 2001 From: Ed Paradis Date: Tue, 18 Aug 2020 20:38:29 -0700 Subject: [PATCH] mention that the 'fullspec' version has more bidrectional lines --- Transceiver-Comparison.md | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/Transceiver-Comparison.md b/Transceiver-Comparison.md index f67e620..1cd5759 100644 --- a/Transceiver-Comparison.md +++ b/Transceiver-Comparison.md @@ -109,4 +109,20 @@ They should probably be Schmitt-trigger inputs on the SCSI bus side. See the "Si 0.5v SCSI Maximum Output Voltage for Asserted Signal 0.2v Typical Driver-Asserted Signal +From [the 2.x schematic](https://github.com/akuker/RASCSI/blob/master/hw/rascsi_2p1/rascsi_2p1_sch.pdf), all signals are bidirectional, switched on three different signals. + +Switched by `PI-DTD`: + +> DP, D0, D1, D2, D3, D4, D5, D6, D7 + +Switched by `PI-TAD`: + +> BSY, MSG, C_D, REQ, I_O + +Switched by `PI-IND`: + +> ATN, ACK, RST, SEL + +### Notes + (1) [Comment by `saybur`](https://68kmla.org/forums/index.php?app=forums&module=forums&controller=topic&id=30399&page=7&tab=comments#comment-646496)