pk8020: fixed keyboard (broken since 0.143). Updated notes.

src/mame/drivers/pk8020.cpp

@@ -11,11 +11,17 @@ Cassette is "best guess", as I was unable to locate any recordings, and
 also do not know the commands to save and load. SAVE and LOAD appear when
 F2 or shift-F2 pressed (in Korvet), but only produce errors.
 
-Status as at 2019-07-19:
-Korvet - can boot CP/M, but the keyboard then doesn't work.
-Neiva - keyboard not working
-BK8T - keyboard not working, stuck at a "config" screen.
-Kontur - needs to boot from a floppy and we don't have any that work
+Status as at 2019-09-18:
+Korvet, Neiva - largely working. Error after running something from B drive.
+              - floppy operation is very slow.
+Kontur - needs to boot from a floppy, not working.
+BK8T - Keys to navigate initial config screen are mostly unknown
+       (space - change value; Esc - go to next screen).
+     - Next screen: wants the date and time. You can press enter here.
+     - Wait a while, ignore the big message. You get a menu.
+     - Press 1 for a typewriter thing, or 6 for another menu.
+     - Not sure about the choices; needs someone who can read Russian.
+
 
 ****************************************************************************/
 

src/mame/machine/pk8020.cpp

@@ -233,5 +233,5 @@ void pk8020_state::machine_reset()
 INTERRUPT_GEN_MEMBER(pk8020_state::pk8020_interrupt)
 {
 	m_takt ^= 1;
-	m_inr->ir4_w(1);
+	m_inr->ir4_w(m_takt);
 }