From 48f836e5c084b5251f4a755167585adcf6f1ba80 Mon Sep 17 00:00:00 2001 From: arbee Date: Wed, 5 Jul 2023 10:46:50 -0400 Subject: devices/ncr53c90.cpp: Don't subtract FIFO contents from transfer count when DMA is started. [R. Belmont] * The 5390/5394/5396 manuals all agree transfer count only decrements on DACK in DMA write mode, and 68040 Macs require it. * Also tested on sun4_60, Solaris boots fine. P-Mac will investigate other uses. --- src/devices/machine/ncr53c90.cpp | 6 ------ 1 file changed, 6 deletions(-) diff --git a/src/devices/machine/ncr53c90.cpp b/src/devices/machine/ncr53c90.cpp index 6f73c28b814..935ad3df145 100644 --- a/src/devices/machine/ncr53c90.cpp +++ b/src/devices/machine/ncr53c90.cpp @@ -1175,12 +1175,6 @@ void ncr53c90_device::clock_w(uint8_t data) void ncr53c90_device::dma_set(int dir) { dma_dir = dir; - - // account for data already in the fifo - if (dir == DMA_OUT && fifo_pos) - { - decrement_tcounter(fifo_pos); - } } void ncr53c90_device::dma_w(uint8_t val) -- cgit v1.2.3