From 9d53a1c4f267c52e1751e6153400ef94765da4e2 Mon Sep 17 00:00:00 2001 From: Adam Date: Thu, 30 Jan 2025 15:29:09 +0100 Subject: [PATCH 1/2] - tek4404 misses signal without a short delay --- src/devices/machine/ncr5385.cpp | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/devices/machine/ncr5385.cpp b/src/devices/machine/ncr5385.cpp index 1045188534532..88de7dab6c321 100644 --- a/src/devices/machine/ncr5385.cpp +++ b/src/devices/machine/ncr5385.cpp @@ -759,6 +759,8 @@ int ncr5385_device::state_step() else m_sbx = false; + delay = 3'500; // >=3.5us delay works, < 3.5us fails + // clear data and ACK scsi_bus->data_w(scsi_refid, 0); scsi_bus->ctrl_w(scsi_refid, 0, S_ACK); From daeac7b08240a0443b6401f35ba3778798ca9c4a Mon Sep 17 00:00:00 2001 From: Adam Date: Thu, 30 Jan 2025 16:18:36 +0100 Subject: [PATCH 2/2] - tweaked comment --- src/devices/machine/ncr5385.cpp | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/src/devices/machine/ncr5385.cpp b/src/devices/machine/ncr5385.cpp index 88de7dab6c321..10a3eaa8855b9 100644 --- a/src/devices/machine/ncr5385.cpp +++ b/src/devices/machine/ncr5385.cpp @@ -759,7 +759,9 @@ int ncr5385_device::state_step() else m_sbx = false; - delay = 3'500; // >=3.5us delay works, < 3.5us fails + // tek4404 fails to load without a delay here + // >=3.5us delay works, < 3.5us fails + delay = 3'500; // clear data and ACK scsi_bus->data_w(scsi_refid, 0);