git.y1.nz

commit 04bac46997dc11ec2721c33c25847adf1a3daec9
parent 8849193ffc7e22511743a4c1b130784e716f5988
Author: bbbbbr <bbbbbr@users.noreply.github.com>
Date:   Mon, 11 Aug 2025 16:55:57 -0700

Duck: changes resulting from printer research and example work (#807)

- Rework printer status functions
- Add printer query function
Diffstat:
M
gbdk-lib/include/duck/laptop_io.h
37
++++++++++++++++++++-----------------
M
gbdk-lib/libc/targets/sm83/duck/megaduck_laptop_io.c
32
+++++++++++++++++++++++---------

2 files changed, 43 insertions(+), 26 deletions(-)
diff --git a/gbdk-lib/include/duck/laptop_io.h b/gbdk-lib/include/duck/laptop_io.h
@@ -35,7 +35,7 @@
 #define DUCK_IO_CMD_ABORT_OR_FAIL             0x04u
 #define DUCK_IO_CMD_PLAY_SPEECH               0x05u
 #define DUCK_IO_CMD_RUN_CART_IN_SLOT          0x08u
-#define DUCK_IO_CMD_PRINT_INIT_MAYBE_EXT_IO   0x09u   /**< Command to init the printer and return status + model type */
+#define DUCK_IO_CMD_PRINT_INIT_EXT_IO         0x09u   /**< Command to init the printer and return status + model type */
 #define DUCK_IO_CMD_SET_RTC                   0x0Bu   /**< Command to set hardware RTC by sending a multi-byte packet */
 #define DUCK_IO_CMD_GET_RTC                   0x0Cu   /**< Command to get hardware RTC by receiving a a multi-byte packet */
 #define DUCK_IO_CMD_PRINT_SEND_BYTES          0x11u   /**< Send printer data */
@@ -90,15 +90,10 @@
 
 // Printer init reply related
 // Init Reply Bit.0
-#define DUCK_IO_PRINTER_INIT_MASK   0x01u // Bit.0
-#define DUCK_IO_PRINTER_INIT_OK     0x01u
-#define DUCK_IO_PRINTER_INIT_FAIL   0x00u
-
-// Init Reply Bit.1
-#define DUCK_IO_PRINTER_TYPE_MASK   0x02u // Bit.1
-#define DUCK_IO_PRINTER_TYPE_2_PASS 0x00u // Bit.1 = 0  // 13 x 12 byte packets + 1 x 5 or 6 byte packet (with CR and/or LF)
+#define DUCK_IO_PRINTER_FAIL        0x00u
+#define DUCK_IO_PRINTER_TYPE_2_PASS 0x01u // Bit.1 = 0  // 13 x 12 byte packets + 1 x 5 or 6 byte packet (with CR and/or LF)
 #define DUCK_IO_PRINTER_TYPE_1_PASS 0x02u // Bit.1 = 1  // 3 x 12 byte packets + 118 non-packet bytes
-
+#define DUCK_IO_PRINTER_MAYBE_BUSY  0x03u // Maybe indicating that Printer Type 1 is busy?
 
 
 extern volatile bool    duck_io_rx_byte_done;
@@ -168,24 +163,32 @@ void duck_io_enable_read_byte(void);
 bool duck_io_laptop_init(void);
 
 
-/** Returns whether the MegaDuck Printer was detected during duck_io_laptop_init()
+/** Returns status of MegaDuck Printer as last detected by duck_io_laptop_init() or duck_io_printer_query()
 
-    Returns `true` if successful, otherwise `false`
+    Returned unsigned 8 bit value will have:
+    \li @ref Bit 0: Printer Status. Mask with @ref DUCK_IO_PRINTER_INIT_OK
+    \li @ref Bit 1: Printer Type. Mask with @ref DUCK_IO_PRINTER_TYPE_MASK
 
     @ref duck_io_laptop_init() must be called first
 */
-bool duck_io_printer_detected(void);
+uint8_t duck_io_printer_last_status(void);
+
+
+/** Performs a 3 x printer query serial command and returns raw system printer reply
 
+    Should be called immediately before trying to print
 
-/** Returns which type of MegaDuck Printer was detected during duck_io_laptop_init()
+    Returned unsigned 8 bit value will have:
+    \li @ref Bit 0: Printer Status. Mask with @ref DUCK_IO_PRINTER_INIT_OK
+    \li @ref Bit 1: Printer Type. Mask with @ref DUCK_IO_PRINTER_TYPE_MASK
 
-    Return value should be one of the following:
-    \li @ref DUCK_IO_PRINTER_TYPE_1_PASS (single pass monochrome)
-    \li @ref DUCK_IO_PRINTER_TYPE_2_PASS (two pass possibly supports shades of grey)
+    The resulting value will be cached and used for
+    any subsequent duck_io_printer_detected() and 
+    duck_io_printer_type() calls.
 
     @ref duck_io_laptop_init() must be called first
 */
-uint8_t duck_io_printer_type(void);
+uint8_t duck_io_printer_query(void);
 
 
 // ===== Higher level IO functions =====
diff --git a/gbdk-lib/libc/targets/sm83/duck/megaduck_laptop_io.c b/gbdk-lib/libc/targets/sm83/duck/megaduck_laptop_io.c
@@ -19,7 +19,7 @@ volatile uint8_t duck_io_rx_byte;
  uint8_t duck_io_tx_buf[DUCK_IO_LEN_TX_MAX];
  uint8_t duck_io_tx_buf_len;
 
- uint8_t duck_io_priniter_init_result = DUCK_IO_PRINTER_INIT_FAIL;  // Default printer to not connected
+ uint8_t duck_io_priniter_init_result = DUCK_IO_PRINTER_FAIL;  // Default printer to not connected
 
 
 static void _delay_1_msec(void);
@@ -143,8 +143,8 @@ bool duck_io_send_cmd_and_buffer(uint8_t io_cmd) {
     }
 
     // Send buffer length + 2 (for length header and checksum bytes)
-    _delay_1_msec;  // Delay for unknown reasons (present in system rom)
-        if (!duck_io_send_byte_and_check_ack_msecs_timeout(packet_length, DUCK_IO_TIMEOUT_200_MSEC, DUCK_IO_REPLY_SEND_BUFFER_OK)) {
+    _delay_1_msec;  // Delay, perhaps for byte serial transfer time? (present in system rom)
+    if (!duck_io_send_byte_and_check_ack_msecs_timeout(packet_length, DUCK_IO_TIMEOUT_200_MSEC, DUCK_IO_REPLY_SEND_BUFFER_OK)) {
         IE_REG = int_enables_saved;
         return false;
     }
@@ -303,9 +303,10 @@ bool duck_io_laptop_init(void) {
     // Initialize Serially attached peripheral
     duck_io_init_ok = duck_io_controller_init();
     if (duck_io_init_ok) {
+
         // Save response from some command
         // (so far not seen being used in System ROM 32K Bank 0)
-        duck_io_send_byte(DUCK_IO_CMD_PRINT_INIT_MAYBE_EXT_IO);
+        duck_io_send_byte(DUCK_IO_CMD_PRINT_INIT_EXT_IO);
 
         // TODO: This wait with no timeout is how the System ROM does it,
         //       but it can probably be changed to a long delay and
@@ -323,12 +324,25 @@ bool duck_io_laptop_init(void) {
 }
 
 
-bool duck_io_printer_detected(void) {
-    return (duck_io_priniter_init_result & DUCK_IO_PRINTER_INIT_OK);
+uint8_t duck_io_printer_last_status(void) {
+    return (duck_io_priniter_init_result);
 }
 
 
-uint8_t duck_io_printer_type(void) {
-    return (duck_io_priniter_init_result & DUCK_IO_PRINTER_TYPE_MASK);
-}
+uint8_t duck_io_printer_query(void) {
 
+    // Query three times in a row, per System ROM behavior
+    // Might be doing some kind of initialization/test
+    for (uint8_t c = 0u; c < 3u; c++) {
+        // Delay per system rom behavior
+        delay(50);
+        duck_io_send_byte(DUCK_IO_CMD_PRINT_INIT_EXT_IO);
+        duck_io_read_byte_with_msecs_timeout(200);
+
+        // Cache result
+        duck_io_priniter_init_result = duck_io_rx_byte;
+        // Fail if the printer is not detected and/or not available
+        if (duck_io_rx_byte == 0) return duck_io_rx_byte;
+    }
+    return duck_io_rx_byte;
+}

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