wd33c9x: Add support for the Translate Address command

Author: startaq

src/devices/machine/wd33c9x.cpp

@@ -807,6 +807,38 @@ void wd33c9x_base_device::start_command()
 		step(false);
 		break;
 
+	case COMMAND_CC_TRANSLATE_ADDRESS:
+		LOGMASKED(LOG_COMMANDS, "Translate Address Command\n");
+		{
+			uint8_t total_sectors = m_regs[CDB_1];
+			uint8_t total_heads = m_regs[CDB_2];
+			uint16_t total_cylinders = m_regs[CDB_3] << 8 | m_regs[CDB_4];
+			uint32_t lba = (m_regs[CDB_5] << 24) | (m_regs[CDB_6] << 16) | (m_regs[CDB_7] << 8) | (m_regs[CDB_8] << 0);
+
+			LOGMASKED(LOG_COMMANDS, "total_sectors=%02x, total_heads=%02x, total_cylinders=%04x, lba=%08x\n", total_sectors, total_heads, total_cylinders, lba);
+
+			uint16_t cylinder = lba / (total_sectors * total_heads);
+			uint8_t head = (lba - (cylinder * total_sectors * total_heads)) / total_sectors;
+			uint8_t sector = (lba - (cylinder * total_sectors * total_heads)) % total_sectors;
+
+			LOGMASKED(LOG_COMMANDS, "-> cylinder=%04x, head=%02x, sector=%02x\n", cylinder, head, sector);
+
+			m_regs[CDB_9] = sector;
+			m_regs[CDB_10] = head;
+			m_regs[CDB_11] = cylinder >> 8;
+			m_regs[CDB_12] = cylinder >> 0;
+
+			m_regs[AUXILIARY_STATUS] &= ~(AUXILIARY_STATUS_CIP | AUXILIARY_STATUS_BSY);
+
+			if (cylinder >= total_cylinders)
+				irq_fifo_push(SCSI_STATUS_LOGICAL_ADDRESS_TOO_LARGE);
+			else
+				irq_fifo_push(SCSI_STATUS_TRANSLATE_SUCCESS);
+
+			update_irq();
+		}
+		break;
+
 	case COMMAND_CC_TRANSFER_INFO:
 		LOGMASKED(LOG_COMMANDS, "Transfer Info Command\n");
 		if (m_mode != MODE_I) {