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Clear the (D)HGR display before showing it, so we don't see garbage

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during startup.

Clear keyboard strobe before exiting.
This commit is contained in:
kris 2019-06-20 21:23:18 +01:00
parent 7d041a6a84
commit b0e83d2faf
1 changed files with 17 additions and 10 deletions
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27
player/main.s
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@ -58,6 +58,7 @@ zpdummy = $08
dummy = $ffff
ptr = $06 ; TODO: we only use this for connection retry count
HGRZP = $E6 ; ZP location used by HGR internals to track page to clear
; soft-switches
KBD = $C000
@ -74,7 +75,7 @@ DHIRESON = $C05E
; MONITOR SUBROUTINES
HGR = $F3E2
HGR0 = $F3EA ; internal entry point within HGR that doesn't set soft-switches
HGR0 = $F3F2 ; internal entry point within HGR that doesn't set soft-switches
COUT = $FDED
PRBYTE = $FDDA
PRNTAX = $F941
@ -311,30 +312,35 @@ op_header:
; Initialize (D)HGR in the CODE segment so we don't accidentally toast ourselves when
; erasing HGR
_op_header_hgr:
; Co-opt HGR internals to clear screen without displaying it.
; nukes the startup code we placed in HGR segment
STA HIRESON
STA FULLSCR
LDA #$20
STA HGRZP ; ZP location used by HGR to track page to clear
JSR HGR0
LDA WDATA ; Video mode
BEQ @1 ; 0 = HGR mode
; TODO: clear screen before displaying it to look cleaner
; DHGR mode
STA TEXTOFF
STA HIRESON
STA DHIRESON
STA COL80ON
STA STORE80ON
; Clear aux screen
STA PAGE2ON ; AUX memory active
; Co-opt HGR internals to clear AUX for us.
LDA #$20
STA HGRZP
JSR HGR0
STA PAGE2OFF ; MAIN memory active
STA TEXTOFF ; now display empty (D)HGR screen. Doing this before the next instruction to make sure we don't see 80-column text garbage momentarily.
STA COL80ON
STA DHIRESON
@1:
JSR HGR ; nukes the startup code we placed in HGR segment
STA FULLSCR
STA TEXTOFF ; now display empty HGR screen (NOP for DHGR since we've already done it)
; establish invariants expected by decode loop
LDY #>RXBASE ; High byte of socket 0 receive buffer
@ -1278,6 +1284,7 @@ op_terminate:
LDA KBD
BPL @0
@1: ; key pressed
LDA KBDSTRB ; clear strobe
JMP exit
; Manage W5100 socket buffer and ACK TCP stream.