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FPGAmstrad

1,004 bytes added, 06:26, 18 October 2017
/* Instruction timing : talk about r005.8.16c4 */
About testbench border effects, I think that IO_ACKed instructions has to be under same rules (MEM_wr, modulo 4 etc) - update : same result in testbench using this way.
 
==== Instruction timing : talk about r005.8.16c20 ====
I try on this version to get an intelligent IO_ACK: in JavaCPC instructions just has a fixed time (array of instruction timing) and IO_ACK does not influence on them. So IO_ACK perhaps has to remove one WAIT_n inserted by GateArray.
 
I have regressions on this version, Still Rising's scroll, and Trail Blazer palette offset at left.
 
"RET cc" instruction seems not respecting original timing in T80. I had 2 clocks in last TStates of it.
 
I don't understand why I have to add 2 WAIT_n when 1 WAIT_n seems suffisant, I think there is some problem around my "PLEASE_WAIT" component (hack of T80's WAIT_n entry), perhaps finally T80's WAIT_n entry is fine, as finally I just insert a certain number of WAIT_n during second clock of M1, MEM_wr slow is unvalidated : Gatearray of Amstrad doesn't have the needed "WR" wire, so.
 
Next step shall be destroying "PLEASE_WAIT" component I think, in order to add 1 WAIT_n and not 2 with my WAIT_n generator.
=== Test of a real Zilog 80 ===
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