WB_IDE - Wishbone IDE Interface Controller
Figure 1. WB_IDE - Wishbone IDE Interface Controller.
The WB_IDE is a Wishbone-compliant peripheral that provides the control interface between an IDE-compatible storage device, such as a hard disk or Compact Flash memory card, and a processor in the FPGA design.
Data can be transferred using one of the supported PIO (Programmed Input/Output) modes – with programmable timing. A direct memory access (DMA) interface can also be used to transfer a 512 byte sector between external memory and the IDE storage device. Such a transfer is initiated by the processor, but then proceeds without processor assistance – allowing the processor to concentrate on other tasks. Note however that memory DMA in this instance is not the same as DMA or UDMA modes associated with hard drives. When using memory DMA, transfer between the WB_IDE and the IDE storage device is still performed using one of the PIO modes.
The WB_IDE also provides powerdown support, which is of particular importance when removing/inserting Compact Flash cards that are not 'hot-swappable'.
Altium's Mass Storage Peripheral Board PB02 provides three ATA (IDE) interfaces – 1.8", 2.5" and 3.5" – as well as a Compact Flash card reader. For more information, see PB02 Mass Storage Peripheral Board.
Features at-a-glance
- Interface control to IDE-compatible storage devices (hard disks, Compact Flash memory cards)
- Support for PIO modes 0 to 4 (without
IORDYflow control)
- 32-bit DMA (Direct Memory Access) interface for 512 byte sector transfers
- Powerdown support
- Wishbone-compliant
Availability
From an OpenBus System document, the IDE Controller component can be found in the Peripherals region of the OpenBus Palette panel.
From a schematic document, the WB_IDE component can be found in the FPGA Peripherals (Wishbone) integrated library (FPGA Peripherals (Wishbone).IntLib), located in the \Library\Fpga folder of the installation.
Designing with the WB_IDE
Use the following links to explore use of the WB_IDE in more detail: