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JiffyDOS NTSC fixes and screen blanking for transfer speedup

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FeralChild64 committed 2019-12-06 20:18:43 +01:00
1 parent d77887041f
commit 899b2e748f
15 files changed
+18 -5
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c64/,,config_generic.s
+1
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@@ -41,6 +41,7 @@
// I/O devices
#define CONFIG_IEC
#define CONFIG_IEC_BLANK_SCREEN
#define CONFIG_IEC_JIFFYDOS
// #define CONFIG_TAPE_NORMAL // please keep disabled for now
#define CONFIG_TAPE_TURBO
c64/,,config_mega65.s
+1
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@@ -43,6 +43,7 @@
// I/O devices
#define CONFIG_IEC
#define CONFIG_IEC_BLANK_SCREEN
#define CONFIG_IEC_JIFFYDOS
// #define CONFIG_TAPE_NORMAL // please keep disabled for now
// #define CONFIG_TAPE_TURBO
c64/,,config_testing.s
+1
View File
@@ -42,6 +42,7 @@
// I/O devices
#define CONFIG_IEC
// #define CONFIG_IEC_BLANK_SCREEN
#define CONFIG_IEC_JIFFYDOS
// #define CONFIG_TAPE_NORMAL // please keep disabled for now
#define CONFIG_TAPE_TURBO
c64/,,config_ultimate64.s
+1
View File
@@ -41,6 +41,7 @@
// I/O devices
#define CONFIG_IEC
#define CONFIG_IEC_BLANK_SCREEN
#define CONFIG_IEC_JIFFYDOS
// #define CONFIG_TAPE_NORMAL // please keep disabled for now
#define CONFIG_TAPE_TURBO
c64/kernal/iec/iec_wait1ms.s
+2
View File
@@ -29,6 +29,8 @@ wait_x_bars: // additional entry point for tape support
dex
bne !-
iec_wait_rts: // dummy RTS, for very short waits
rts
c64/kernal/iec_fast/load_jiffydos.s
+8 -5
View File
@@ -3,8 +3,6 @@
// JiffyDOS protocol support for IEC - optimized load loop
//
// XXX option does not work yet
// #define CONFIG_IEC_BLANK_SCREEN
#if CONFIG_IEC_JIFFYDOS && !CONFIG_MEMORY_MODEL_60K
@@ -61,6 +59,10 @@ load_jiffydos_loop:
#if CONFIG_IEC_BLANK_SCREEN
// It JiffyDOS needs some time here; waste few cycles
nop
jsr iec_wait_rts
// Ask device to start sending bits
sta CIA2_PRA
@@ -87,8 +89,8 @@ load_jiffydos_loop:
lsr
lsr
// Wait for the drive - we have time to increment offset, cycles: 2
iny
// Delay, JiffyDOS needs some time, 2 cycles
nop
// Get bits, cycles: 4 + 2 + 2 = 8
ora CIA2_PRA // bits 2 and 3 on CLK/DATA
@@ -105,7 +107,8 @@ load_jiffydos_loop:
eor C3PO
eor CIA2_PRA // bits 6 and 7 on CLK/DATA
// Store retrieved byte, cycles: 6
// Store retrieved byte, cycles: 2 + 6 = 8
iny // NTSC needs this delay
sta (EAL),y // not compatible with CONFIG_MEMORY_MODEL_60K
// Retrieve status bits, cycles: 4