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robustness improvements in IEC support

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FeralChild64 committed 2019-06-22 14:35:28 +02:00
1 parent b21ce3116d
commit 22e1e201af
11 files changed
+63 -12
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c64/kernal/iec_pull_atn_clk_release_data.s
+10 -2
View File
@@ -1,7 +1,15 @@
iec_pull_atn_clk_release_data:
;; Pulled CLK = DATA considered invalid; for extra robustness on non-emulated
;; hardware give some lines few more cycles to stabilize; see page 10 of
;; http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
lda CI2PRA
ora #BIT_CI2PRA_ATN_OUT + BIT_CI2PRA_CLK_OUT ; pull
and #$FF - BIT_CI2PRA_DAT_OUT ; release
ora #BIT_CI2PRA_ATN_OUT ; pull
sta CI2PRA
ora #BIT_CI2PRA_CLK_OUT ; pull
sta CI2PRA
and #$FF - BIT_CI2PRA_DAT_OUT ; release
sta CI2PRA
rts
c64/kernal/iec_pull_clk_release_data.s
+6
View File
@@ -1,7 +1,13 @@
iec_pull_clk_release_data:
;; Pulled CLK = DATA considered invalid; for extra robustness on non-emulated
;; hardware give some lines few more cycles to stabilize; see page 10 of
;; http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
lda CI2PRA
ora #BIT_CI2PRA_CLK_OUT ; pull
sta CI2PRA
and #$FF - BIT_CI2PRA_DAT_OUT ; release
sta CI2PRA
rts
c64/kernal/iec_pull_data_release_atn_clock.s
+11 -3
View File
@@ -1,7 +1,15 @@
iec_pull_data_release_atn_clock:
iec_pull_data_release_atn_clk:
;; Released CLK = DATA considered valid; for extra robustness on non-emulated
;; hardware give some lines few more cycles to stabilize; see page 10 of
;; http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
lda CI2PRA
ora #BIT_CI2PRA_DAT_OUT ; pull
and #$FF - BIT_CI2PRA_ATN_OUT - BIT_CI2PRA_CLK_OUT ; release
ora #BIT_CI2PRA_DAT_OUT ; pull
sta CI2PRA
and #$FF - BIT_CI2PRA_CLK_OUT ; release
sta CI2PRA
and #$FF - BIT_CI2PRA_ATN_OUT ; release
sta CI2PRA
rts
c64/kernal/iec_release_atn_clk_data.s
+10 -1
View File
@@ -1,7 +1,16 @@
iec_release_atn_clk_data:
;; Released CLK = DATA considered valid; for extra robustness on non-emulated
;; hardware give some lines few more cycles to stabilize; see page 10 of
;; http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
lda CI2PRA
and #$FF - BIT_CI2PRA_ATN_OUT - BIT_CI2PRA_CLK_OUT - BIT_CI2PRA_DAT_OUT ; release
and #$FF - BIT_CI2PRA_ATN_OUT ; release
sta CI2PRA
and #$FF - BIT_CI2PRA_DAT_OUT ; release
sta CI2PRA
and #$FF - BIT_CI2PRA_CLK_OUT ; release
sta CI2PRA
rts
c64/kernal/iec_release_clk_data.s
+8 -1
View File
@@ -1,6 +1,13 @@
iec_release_clk_data:
;; Released CLK = DATA considered valid; for extra robustness on non-emulated
;; hardware give some lines few more cycles to stabilize; see page 10 of
;; http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
lda CI2PRA
and #$FF - BIT_CI2PRA_CLK_OUT - BIT_CI2PRA_DAT_OUT ; release
and #$FF - BIT_CI2PRA_DAT_OUT ; release
sta CI2PRA
and #$FF - BIT_CI2PRA_CLK_OUT ; release
sta CI2PRA
rts
c64/kernal/iec_release_clk_pull_data.s
+7 -1
View File
@@ -1,7 +1,13 @@
iec_release_clk_pull_data:
;; Released CLK = DATA considered valid; for extra robustness on non-emulated
;; hardware give some lines few more cycles to stabilize; see page 10 of
;; http://www.zimmers.net/anonftp/pub/cbm/programming/serial-bus.pdf
lda CI2PRA
and #$FF - BIT_CI2PRA_CLK_OUT ; release
ora #BIT_CI2PRA_DAT_OUT ; pull
sta CI2PRA
and #$FF - BIT_CI2PRA_CLK_OUT ; release
sta CI2PRA
rts
c64/kernal/iec_turnaround_to_listen.s
+1 -1
View File
@@ -5,7 +5,7 @@
iec_turnaround_to_listen:
;; Pull DATA, release CLK and ATN (we are not sending commands)
jsr iec_pull_data_release_atn_clock
jsr iec_pull_data_release_atn_clk
;; Wait for clock line to be pulled by the drive
ldx #$FF ; XXX should we really use that high number?
c64/kernal/listen.s
+3 -1
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@@ -2,6 +2,8 @@
listen:
;; This trivial routine is documented in 'Compute's Mapping the Commodore 64', page 223
;; This trivial routine is documented in 'Compute's Mapping the Commodore 64', page 223 and
;; https://www.pagetable.com/?p=1031, , https://github.com/mist64/cbmbus_doc
and #$1F ; make sure bits encoding the command are cleared out
ora #$20
jmp iec_tx_command
c64/kernal/second.s
+3 -1
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@@ -1,6 +1,8 @@
; Function defined on pp272-273 of C64 Programmers Reference Guide
second:
;; This trivial routine is documented in 'C64 Programmer's Reference Guide', page 296
;; This trivial routine is documented in 'C64 Programmer's Reference Guide', page 296 and
;; https://www.pagetable.com/?p=1031, , https://github.com/mist64/cbmbus_doc
and #$1F ; make sure bits encoding the command are cleared out
ora #$60
jmp iec_tx_command
c64/kernal/talk.s
+3 -1
View File
@@ -2,7 +2,9 @@
talk:
;; This trivial routine is documented in 'Compute's Mapping the Commodore 64', page 223
;; This routine is documented in 'Compute's Mapping the Commodore 64', page 223 and
;; https://www.pagetable.com/?p=1031, , https://github.com/mist64/cbmbus_doc
and #$1F ; make sure bits encoding the command are cleared out
ora #$40
jmp iec_tx_command
c64/kernal/tksa.s
+1
View File
@@ -3,6 +3,7 @@ tksa:
;; This routine is documented in 'C64 Programmer's Reference Guide', page 302 and
;; https://www.pagetable.com/?p=1031, , https://github.com/mist64/cbmbus_doc
and #$1F ; make sure bits encoding the command are cleared out
ora #$F0
jmp iec_tx_command