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FPGAmstrad

36 bytes added, 20:15, 20 July 2011
/* Effort done */
== Effort done ==
'''Instruction timing''' : I tested instruction timing of T80 compare to instruction timing of JavaCPC emulator. I deduce synchronization of Z80 with CRTC on M1 signal by WAIT_n insertion in order to have a multiple of 4 Tstates per instruction. I deduce also one WAIT_n inserted during MEM_WR operation.(yes I log testbench T80, i'm crazy)
'''Test of a real Zilog 80''', in fact the only difference between T80 of opencore and real Z80 is that T80 run on rising_edge, and Z80 run during low state. Test past with little modification of sequencer forcing it do nothing during low state of z80, resulting a clockdown (memory are too overclocked with this sequencer modification), perhaps using buffer on address bus and data bus could solve this detail... but as it runs for me it is not a problem.
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