From 731d666cbd7cd4aa656ad914d492287664c77f33 Mon Sep 17 00:00:00 2001 From: AJR Date: Tue, 7 Jan 2020 11:10:56 -0500 Subject: vt50_cpu: Minor note (nw) --- src/devices/cpu/vt50/vt50.cpp | 3 +++ 1 file changed, 3 insertions(+) diff --git a/src/devices/cpu/vt50/vt50.cpp b/src/devices/cpu/vt50/vt50.cpp index c07d9b44014..d2ed58dde79 100644 --- a/src/devices/cpu/vt50/vt50.cpp +++ b/src/devices/cpu/vt50/vt50.cpp @@ -568,7 +568,10 @@ void vt5x_cpu_device::execute_tj(u8 dest) if (m_load_pc) m_pc = u16(m_rom_page) << 8 | dest; else + { + // Hardware bug: the ROM page counter will not increment on the second byte of a jump not taken. m_pc = (m_pc + 1) & 03777; + } } void vt5x_cpu_device::clock_video_counters() -- cgit v1.2.3