1
0
mirror of https://github.com/sethm/symon.git synced 2024-06-15 08:29:27 +00:00
Commit Graph

4 Commits

Author SHA1 Message Date
Seth Morabito
e2a1144c7c Update copyright, prep for 1.1.0 2014-08-11 14:16:41 -07:00
Seth Morabito
da8250778e Bug Fixes and Copyright Date Change
The simulator now passes Klaus Dormann's 6502 Functional Test suite for
the first time.

Bug Fixes:

- PHP was not correctly setting the Break bit on the stack copy of the
  processor status, so subsequent PLA's would not set the Break status
  flag.

- The CPU had swapped NMI and IRQ reset vectors, so RTI was failing.

- BRK was pushing PC + 2 onto the stack, instead of PC + 1

- (Zero Page,X) addressing mode did not correctly wrap on zero page
  boundaries.

- The instruction table used for disassembly had addressing modes
  of LDA $B9 and $BD reversed. This did not affect behavior, only
  disassembly of these instructions.

Other:

- Updated copyright date for 2013.

- Started migrating old JUnit 3 style tests to JUnit 4 annotations.
2013-01-01 17:03:16 -08:00
Seth Morabito
2ebdd254b3 Work In Progress: CPU behavior, UI changes
This is something of a "Work in Progress" checkpoint of several features
that are all half baked:

1. Allow loading of 16KB ROM files at address $C000 at run-time, not
   just at startup. See the "Load ROM..." File menu item.

2. Introduces the notion of "CPU Behaviors", so the core 6502 CPU
   implementation can match the behavior of either an early NMOS 6502, late
   NMOS 6502, or CMOS 65C02. Very little of this is actually implemented so
   far.

3. Adds a completely bogus implementation of the 6522 VIA (it
   does absolutely nothing right now).

4. Changes the address of the ACIA in the simulated system to match a
   real hardware implementation I put together.
2012-11-25 22:49:21 -08:00
Seth J. Morabito
00ab8cd9ff Simulator is just about ready for real-world testing now. Added a simulated
MOS6551 ACIA at address $C000 which does buffered input and output via the
console. Updated the README with a bit more documentation, and bumped the
version number to 0.1 because I'm impatient.
2010-01-20 18:19:39 -08:00