From dc8c36f9965b6d13197d88d9a84d3386eac483c4 Mon Sep 17 00:00:00 2001 From: hap Date: Thu, 9 Mar 2023 20:54:29 +0100 Subject: ssystem3: remove obsolete workaround --- src/mame/saitek/ssystem3.cpp | 11 ----------- 1 file changed, 11 deletions(-) diff --git a/src/mame/saitek/ssystem3.cpp b/src/mame/saitek/ssystem3.cpp index 202c59b9140..355ccd8166d 100644 --- a/src/mame/saitek/ssystem3.cpp +++ b/src/mame/saitek/ssystem3.cpp @@ -43,11 +43,6 @@ reversi program called "The Moor". The chesscomputer was discontinued soon after release, and none of the accessories or other games came out. TODO: -- 6522 ACR register is initialized with 0xe3. Meaning: PA and PB inputs are set - to latch mode, but the program then never clocks the latch, it functions as if - it meant to write 0xe0. Maybe 6522 CA1 pin emulation is wrong? Documentation - says it's edge-triggered, but here it's tied to VCC. I added a trivial hack to - work around this, see rom defs. - 2nd 7474 /2 clock divider on each 4000-7fff access, this also applies to 6522 clock (doesn't affect chess calculation speed, only I/O access, eg. beeper pitch). Should be doable to add, but 6522 device doesn't support live clock changes. @@ -540,9 +535,6 @@ ROM_START( ssystem3 ) ROM_LOAD("c19081e_ss-3-lrom.u4", 0x8000, 0x1000, CRC(9ea46ed3) SHA1(34eef85b356efbea6ddac1d1705b104fc8e2731a) ) // 2332 ROM_LOAD("c19082_ss-3-hrom.u5", 0x9000, 0x1000, CRC(52741e0b) SHA1(2a7b950f9810c5a14a1b9d5e6b2bd93da621662e) ) // " - // HACK! 6522 ACR register setup - ROM_FILL(0x946d, 1, 0xe0) // was 0xe3 - ROM_REGION(0x10000, "subcpu", 0) ROM_LOAD("c28a97m_ss-3l-rom", 0x4000, 0x0800, CRC(bf0b2a84) SHA1(286f56aca2e50b78ac1fae4a89413659aceb71d9) ) // 2316 @@ -562,9 +554,6 @@ ROM_START( ssystem4 ) ROM_LOAD("c45022_ss4-mrom", 0xe000, 0x1000, CRC(c6110af1) SHA1(4b63454a23b2fe6b5c8f3fa6718eb49770cb6907) ) // " ROM_LOAD("c45023_ss4-hrom", 0xf000, 0x1000, CRC(ab4a4343) SHA1(6eeee7168e13dc1115cb5833f1938a8ea8c01d69) ) // " - // HACK! 6522 ACR register setup - ROM_FILL(0xd05b, 1, 0xe0) // was 0xe3 - ROM_REGION(53552, "screen", 0) // looks same, but different pinout ROM_LOAD("ssystem4.svg", 0, 53552, CRC(b69b12e3) SHA1(c2e39d015397d403309f1c23619fe8abc3745d87) ) ROM_END -- cgit v1.2.3