various I/O updates

c64/kernal/iec/iec_jiffydos.s

@@ -0,0 +1,93 @@
+
+//
+// JiffyDOS protocol support for IEC
+//
+
+// XXX finish this
+
+
+
+#if CONFIG_IEC_JIFFYDOS
+
+
+iec_tx_byte_jiffydos:
+
+	// JiffyDOS timing regime is very strict - before transmitting anything
+	// we need to disable sprites and (if screen is not disabled) wait for
+	// appropriate moment, so that no badline interruption can happen
+	
+	jsr jiffydos_hide_sprites
+	jsr jiffydos_wait_line
+
+__jd_check1:
+
+	// XXX send byte
+
+	// Re-enable sprites
+	jsr jiffydos_restore_sprites
+
+	rts
+	
+
+iec_rx_byte_jiffydos:
+
+	// JiffyDOS timing regime is very strict - before transmitting anything
+	// we need to disable sprites and (if screen is not disabled) wait for
+	// appropriate moment, so that no badline interruption can happen
+	
+	jsr jiffydos_hide_sprites
+	jsr jiffydos_wait_line
+
+	// XXX retrieve byte
+
+	// Re-enable sprites
+	jsr jiffydos_restore_sprites
+
+	rts
+
+
+jiffydos_wait_line:
+
+	// XXX if screen not disabled, wait for badline to pass
+
+	rts
+
+
+__jd_check2:
+	
+	
+jiffydos_hide_sprites:
+
+	// XXX implement
+	
+	rts
+
+
+jiffydos_restore_sprites:
+
+	// XXX implement
+	
+	rts
+
+
+.function SAME_PAGE_CHECK(label_1, label_2)
+{
+#if !PASS_SIZETEST
+	return (label_1 - label_1 % 256) == (label_2 - label_2 % 256)
+#else
+	return true
+#endif
+}
+
+.if (!SAME_PAGE_CHECK(__jd_check1, __jd_check2))
+{
+	// To meet the strict JiffyDOS timing, we need to make sure
+	// it does not span across multiple pages, as this would add
+	// 1 cycle to some jump instructions - maybe this wont cause
+	// problems, but better safe than sorry.
+
+	.error "JiffyDOS code can't span across multiple pages"
+}
+
+
+#endif // CONFIG_IEC_JIFFYDOS

c64/kernal/iec/save_iec.s

@@ -0,0 +1,37 @@
+
+//
+// IEC part of the SAVE routine
+//
+
+
+#if CONFIG_IEC
+
+
+save_iec:
+
+/*
+	// Display SAVING
+	// XXX jsr lvs_display_saving
+
+	// Call device to LISTEN
+	lda FA
+	jsr LISTEN
+	bcs save_iec_dev_not_found // XXX redirecto to load
+
+	// Open channel XXX (reserved for file writing)
+	lda #XXX
+	jsr iec_cmd_open
+	bcs // XXX error
+
+	// Send file name
+	jsr lvs_send_file_name
+	bcs load_iec_error
+
+	// XXX finish the implementation
+	
+	rts
+*/
+
+	STUB_IMPLEMENTATION()
+
+#endif // CONFIG_IEC