From c307ec2a16393205b2da9539839fefa90b397772 Mon Sep 17 00:00:00 2001 From: hap Date: Thu, 12 Mar 2015 13:00:26 +0100 Subject: improve ebball3 clock --- src/mess/drivers/hh_tms1k.c | 10 +++++----- src/mess/layout/hh_hmcs40_test.lay | 4 +++- src/mess/layout/hh_ucom4_test.lay | 4 +++- 3 files changed, 11 insertions(+), 7 deletions(-) diff --git a/src/mess/drivers/hh_tms1k.c b/src/mess/drivers/hh_tms1k.c index b08aecb903b..28477f781ff 100644 --- a/src/mess/drivers/hh_tms1k.c +++ b/src/mess/drivers/hh_tms1k.c @@ -1058,10 +1058,10 @@ INPUT_PORTS_END void hh_tms1k_state::ebball3_set_clock() { - // MCU clock is from an RC circuit oscillating by default at ~375kHz, - // but on PRO, the difficulty switch adds an extra capacitor to Vdd to speed - // it up to unknown, let's assume ~425kHz. - m_maincpu->set_unscaled_clock(m_inp_matrix[3]->read() & 1 ? 425000 : 375000); + // MCU clock is from an RC circuit(R=47K, C=33pf) oscillating by default at ~340kHz, + // but on PRO, the difficulty switch adds an extra 150K resistor to Vdd to speed + // it up to around ~440kHz. + m_maincpu->set_unscaled_clock(m_inp_matrix[3]->read() & 1 ? 440000 : 340000); } INPUT_CHANGED_MEMBER(hh_tms1k_state::ebball3_difficulty_switch) @@ -1078,7 +1078,7 @@ MACHINE_RESET_MEMBER(hh_tms1k_state, ebball3) static MACHINE_CONFIG_START( ebball3, hh_tms1k_state ) /* basic machine hardware */ - MCFG_CPU_ADD("maincpu", TMS1100, 375000) // RC osc. R=47K, C=33pf -> ~375kHz + MCFG_CPU_ADD("maincpu", TMS1100, 340000) // see ebball3_set_clock MCFG_TMS1XXX_READ_K_CB(READ8(hh_tms1k_state, ebball3_read_k)) MCFG_TMS1XXX_WRITE_R_CB(WRITE16(hh_tms1k_state, ebball3_write_r)) MCFG_TMS1XXX_WRITE_O_CB(WRITE16(hh_tms1k_state, ebball3_write_o)) diff --git a/src/mess/layout/hh_hmcs40_test.lay b/src/mess/layout/hh_hmcs40_test.lay index 20bf5b22243..55266384f2e 100644 --- a/src/mess/layout/hh_hmcs40_test.lay +++ b/src/mess/layout/hh_hmcs40_test.lay @@ -5,9 +5,11 @@ - + + + diff --git a/src/mess/layout/hh_ucom4_test.lay b/src/mess/layout/hh_ucom4_test.lay index 20bf5b22243..55266384f2e 100644 --- a/src/mess/layout/hh_ucom4_test.lay +++ b/src/mess/layout/hh_ucom4_test.lay @@ -5,9 +5,11 @@ - + + + -- cgit v1.2.3