1. NS Training Hardware

2. USB 2.0

3. USB Overview

4. USB Device Full Speed (12Mbps) or Low Speed (1.5Mbps)
One bi-directional control EP (end point) and 11 unidirectional programmable EP’s
Supported by a DMA controller
Select either Usb Host or Device

5. USB Device Hardware Configuration
Negotiate/Configure
DMA Setup/Completion
Handle Transaction Errors

6. Negotiate/Configure
Respond to Get Device Configuration Setup Command (see
Device HW Naks until an IN DMA on Channel zero is created
After Set Device Configuration Setup Command interrupt occurs, read CFG, INTF, and ALT (0x9010_0004) and program endpoint registers (0x9010_ x9010_3150)

7. DMA Setup/Completion
Enable DMA In or Out depending on CIA selected by Usb Host
Fifo/DMA 0 is OUT on Control port, DMA 1 is IN, remainder correspond to Endpoints 1..11
Enable DMA completion and error interrupts for each channel [GLBL_EN, GBL_DMA, FIFO, URST, ERR(0-2), NAK(0-2), UFLOW(0-2), OFLOW(0-2)]
Ack interrupt complete by writing ECIP of interrupt status register

8. Handle Transaction Errors
Read ECIP to determine if error occurred.
If error on IN DMA (to host):
Read in packet counter PKTCNT
Increment DMA start pointer by that many packets (start += PKTCNT * MAXPKTSZ), and decrement length by that amount
Write buffer REFETCH bit
Take the channel/Fifo out of reset (write status.CLR to 0)

9. Transaction error If OUT DMA Error:
NS9750 will close all outstanding DMA buffers on this channel (with error)
User should read PKTCNT and setup a new DMA buffer starting at PKTCNT+MAXPKTSZ (since PKTCNT –1 ok transactions)
??Take channel Fifo out of reset ???

10. USB Host Follows OHCI 1.0a programming model
See
Compatible with Full and low speed devices
Provides current relay pin for power management of connected device

11. USB Host Operation Initialize OHCI Wait for devices to attach
Transfer Descriptor Setup/Complete

12. OHCI Initialization Wait for NS9750 UsbHost to come out of reset
Allocate an HCCA structure
Create blank TD and ED for Bulk, Isochronous, Interrupt and Control queues
Enable OHCI interrupt in NS9750
Set FrameInterval and HcPeriodic Start
Set up Root Hub (eg GoodToGo, PowerSwitching and OverCurrentProtection)

13. OHCI Setup Host Controller Registers start at 0x0900_1000
User must set up HCCA and maintain Endpoint descriptors and Transfer Descriptors
Only one interrupt: OHCI_IRQ

14. Wait for device to attach
Standard OHCI, wait for port CCS, then reset the attached device, then start GET DEVICE DESCRIPTOR transfer.
Application sends above transfer and then sends a SET CONIFGURATION and SET INTERFACE transfer.
From the selected CIA, add Endpoint descriptors to appropriate OCHI schedule table

15. Transfer Descriptor Setup/Complete
Follows standard OCHI model
Setup TDs as requested by app.
Handle Done queue interrupts to retire TDs and free TD memory.

16. Hints & Kinks Can the USB Host and Device work at the same time?No
Are Usb 2.0 Devices supported?
USB 2.0 Low and Full speed devices are. In addition, USB 1.1 devices are supported.
Does the USB Host supply power?
Not from the NS9750.