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FPGAmstrad

781 bytes added, 20:40, 13 May 2017
/* TODO : refactor of Parrot PAL signal */
Done in r005.8.14.1
==== TODO DONE : refactor of Parrot PAL signal ====
I found a running 15kHz TV, with [http://github.com/mist-devel/mist-board/blob/master/tutorials/soc/lesson11/lesson11.png mist-board tutorial lesson11 Parrot PAL] running fine, but not with CoreAmstrad r005.8.14.1. It's the same TV I used some years ago at festival with original CPC. I have to refactor Parrot tutorial and adapt it on CoreAmstrad in order to generate a better TV signal quality.
 
Done in r005.8.14.2
 
In theory, simple_GateArrayInterrupt.vhd shall have :
vsync_azrael<=etat_monitor_vhsync(2);
hsync_azrael<=etat_monitor_hsync(2);
if hSyncCount=2+4 then
In practice - in r005.8.14.2 - here we have :
vsync_azrael<=etat_monitor_vhsync(1);
hsync_azrael<=etat_monitor_hsync(1);
if hSyncCount=1+4 then
This way screen is nicely centered but CPCWiki rule "The HSYNC is modified before being sent to the monitor. It happens 2us after the HSYNC from the CRTC and lasts 4us when HSYNC length is greater or equal to 6. If R2=46, and HSYNC width is 14 then monitor hsync starts at 48 and lasts until 51." is not respected.
 
Test about centering screen are done using "BORDER 0", this way border is ignored and does interact with HSYNC/VSYNC screen synchronisation.
=== DONE : CRTC1 ===
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