apple2: Capture all edges of WDATA

Author: keirf

inc/floppy.h

@@ -22,6 +22,12 @@
 #define is_quickdisk FALSE
 #endif
 
+#if defined(APPLE2)
+#define WDATA_TOGGLE TRUE
+#else
+#define WDATA_TOGGLE FALSE
+#endif
+
 #define FINTF_SHUGART     0
 #define FINTF_IBMPC       1
 #define FINTF_IBMPC_HDOUT 2

src/floppy_generic.c

@@ -294,7 +294,7 @@ static void timer_dma_init(void)
     tim_wdata->psc = (SYSCLK_MHZ/SAMPLECLK_MHZ) - 1;
     tim_wdata->arr = 0xffff;
     tim_wdata->ccmr1 = TIM_CCMR1_CC1S(TIM_CCS_INPUT_TI1);
-    tim_wdata->dier = TIM_DIER_CC1DE;
+    tim_wdata->dier = TIM_DIER_CC1DE | (WDATA_TOGGLE ? TIM_DIER_CC1IE : 0);
     tim_wdata->cr2 = 0;
 
     /* DMA setup: From the WDATA Timer's CCRx into a circular buffer. */

src/gotek/floppy.c

@@ -53,20 +53,28 @@ DEFINE_IRQ(dma_wdata_irq, "IRQ_wdata_dma");
 #define dma_rdata_irq DMA1_CH3_IRQ
 DEFINE_IRQ(dma_rdata_irq, "IRQ_rdata_dma");
 
-/* EXTI IRQs. */
-void IRQ_6(void) __attribute__((alias("IRQ_SELA_changed"))); /* EXTI0 */
-void IRQ_7(void) __attribute__((alias("IRQ_WGATE_rotary"))); /* EXTI1 */
-void IRQ_10(void) __attribute__((alias("IRQ_SIDE_changed"))); /* EXTI4 */
-void IRQ_23(void) __attribute__((alias("IRQ_WGATE_rotary"))); /* EXTI9_5 */
+/* Head step handling. */
 #if defined(APPLE2)
 static struct timer step_timer;
 static void POLL_step(void *unused);
 #else
 void IRQ_28(void) __attribute__((alias("IRQ_STEP_changed"))); /* TMR2 */
 #endif
+
+/* EXTI IRQs. */
+void IRQ_6(void) __attribute__((alias("IRQ_SELA_changed"))); /* EXTI0 */
+void IRQ_7(void) __attribute__((alias("IRQ_WGATE_rotary"))); /* EXTI1 */
+void IRQ_10(void) __attribute__((alias("IRQ_SIDE_changed"))); /* EXTI4 */
+void IRQ_23(void) __attribute__((alias("IRQ_WGATE_rotary"))); /* EXTI9_5 */
 void IRQ_40(void) __attribute__((alias("IRQ_MOTOR_CHGRST_rotary"))); /* EXTI15_10 */
+#if WDATA_TOGGLE
+void IRQ_27(void) __attribute__((alias("IRQ_wdata_capture"))); /* TMR1_CC */
+#endif
 #define MOTOR_CHGRST_IRQ 40
 static const struct exti_irq exti_irqs[] = {
+#if WDATA_TOGGLE
+    /* WDATA */ { 27, FLOPPY_IRQ_WGATE_PRI, 0 },
+#endif
     /* SELA */ {  6, FLOPPY_IRQ_SEL_PRI, 0 }, 
 #if !defined(APPLE2)
     /* STEP */ { 28, FLOPPY_IRQ_STEP_PRI, m(2) /* dummy */ },
@@ -532,6 +540,17 @@ static void IRQ_CHGRST(struct drive *drv)
     }
 }
 
+#if WDATA_TOGGLE
+static void IRQ_wdata_capture(void)
+{
+    /* Clear WDATA-captured flag. */
+    (void)tim_wdata->ccr1;
+
+    /* Toggle polarity to capture the next edge. */
+    tim_wdata->ccer ^= TIM_CCER_CC1P;
+}
+#endif
+
 static void IRQ_MOTOR_CHGRST_rotary(void)
 {
     struct drive *drv = &drive;