Pci\ven_1c00&dev_3253&cc_070005 95%

| Field | Value | |-------|-------| | | MosChip MCS3253 / ASIX AX99100? (or similar) | | Chip family | PCIe to dual UART + parallel port controller | | Function | Adds legacy I/O: 2 x RS-232 serial ports + 1 x IEEE1284 parallel port |

After checking up-to-date PCI ID repositories: → Asix Electronics Corporation (formerly MosChip Semiconductor). Asix acquired MosChip's PCIe/PCI I/O controller line. Thus, the actual vendor is ASIX Electronics / MosChip . 3. Device Identification (DEV_3253) DEV_3253 corresponds to: pci\ven_1c00&dev_3253&cc_070005

| Vendor | Details | |--------|---------| | (or Silan Integrated Circuit Co., Ltd.) | A Chinese semiconductor company. However, this specific vendor ID is also widely reused by PLX Technology (now part of Broadcom) for bridge devices, and by various third-party PCIe-to-serial/parallel bridge chips under the MCS (MosChip Semiconductor) or Oxford Semiconductor families. | | Field | Value | |-------|-------| | |

| Byte | Value | Meaning | |------|-------|---------| | Base Class | 0x07 | | | Sub-Class | 0x00 | Serial Port (UART) | | Programming Interface | 0x05 | 16950 compatible (or higher) – indicates high-speed UART with 16650/16950 FIFO support, typically 128-byte FIFOs | Thus, the actual vendor is ASIX Electronics / MosChip

The MCS3253 is a specific part number from MosChip (pre-ASIX acquisition). Later ASIX equivalents: (PCIe to multi-I/O, software compatible).