+typedef void (dcpu16_hw_signal_t)(struct dcpu16 *, struct dcpu16_hw *);
+/* this structure defines a specific instance of this type of 'hardware' */
+struct dcpu16_hw {
+ struct dcpu16 *vm; /* which system do I belong to */
+ struct dcpu16_hw_module *mod; /* whence I came */
+ void *data; /* per-instance data */
+};
+
+/* human-readable text describing hw module control operations, for convenience's sake */
+struct dcpu16_hw_ctl_cmd {
+ char *command;
+ char *data_in_type;
+ char *data_out_type;
+ char *description;
+};
+
+typedef int (dcpu16_hw_data_init_t)(struct dcpu16_hw *, void *);
+typedef void (dcpu16_hw_data_free_t)(struct dcpu16_hw *);
+typedef int (dcpu16_hw_ctl_t)(struct dcpu16_hw *, const char *, void *, void *);
+struct dcpu16_hw_module {
+ char *name_; /* dymo label on front panel */
+
+ DCPU16_WORD id_l;
+ DCPU16_WORD id_h;
+ DCPU16_WORD ver;
+ DCPU16_WORD mfg_l;
+ DCPU16_WORD mfg_h;
+
+ dcpu16_hw_signal_t *hwi; /* hardware interrupt handler */
+ dcpu16_hw_signal_t *cycle; /* cycle tick handler */
+ dcpu16_hw_signal_t *reset; /* reset handler */
+
+ dcpu16_hw_data_init_t *data_init; /* how to allocate a dcpu16_hw instance's data */
+ dcpu16_hw_data_free_t *data_free;
+ dcpu16_hw_ctl_t *ctl;
+ struct dcpu16_hw_ctl_cmd *ctl_cmd;
+};
+
+/* update a message handler */
+dcpu16_msg_cb_t *dcpu16_msg_set(struct dcpu16 *, dcpu16_msg_cb_t *);
+