UM10139

Philips SemiconductorsVolume 1UM10139Chapter 14: USB Device ControllerTable 188: USB Endpoint Interrupt Enable register (USBEpIntEn - address 0xE009 0034) bit descriptionBit Symbol Value Description Reset value31:0 See0 No effect. 0USBEpIntEn1 The corresponding bit in the Endpoint Interrupt Status registerbit allocation(Section 14.7.7) transfers its status to the Device Interrupt Status registertable above(Section 14.7.2). Having a bit in the USBEpIntEn set to 1 implies operatingin the slave mode.14.7.9 USB Endpoint Interrupt Clear register (USBEpIntClr - 0xE009 0038)Writing a 1 to this bit clears the bit in the endpoint interrupt status register. Writing 0 willnot have any impact. When the endpoint interrupt is cleared from this register, thehardware will clear the CDFULL bit in the Device Interrupt Status register. On completionof this action, the CDFULL bit will be set and the Command Data register will have thestatus of the endpoint. Endpoint Interrupt register and CDFULL bit of Device Interruptstatus register are related through clearing of interrupts in USB clock domain. Wheneversoftware attempts to clear a bit of Endpoint Interrupt register, hardware will clear CDFULLbit before it starts issuing "Select Endpoint/Clear Interrupt" command (refer to Section14.9.11 “Select Endpoint/Clear Interrupt (Command: 0x40 - 0x5F, Data: read 1 byte)” onpage 229) and sets the same bit when command data is available for reading. Softwarewill have to wait for CDFULL bit to be set to '1' (whenever it expects data from hardware)before it can read Command Data register. Each physical endpoint has its own reservedbit in this register. The bit field definition is the same as the Endpoint Interrupt StatusRegister as shown in Table 172. The USBEpIntClr is a write only register.Table 189: USB Endpoint Interrupt Clear register (USBEpIntClr - address 0xE009 0038) bit allocationReset value: 0x0000 0000Bit 31 30 29 28 27 26 25 24Symbol EP15TX EP15RX EP14TX EP14RX EP13TX EP13RX EP12TX EP12RXBit 23 22 21 20 19 18 17 16Symbol EP11TX EP11RX EP10TX EP10RX EP9TX EP9RX EP8TX EP8RXBit 15 14 13 12 11 10 9 8Symbol EP7TX EP7RX EP6TX EP6RX EP5TX EP5RX EP4TX EP4RXBit 7 6 5 4 3 2 1 0Symbol EP3TX EP3RX EP2TX EP2RX EP1TX EP1RX EP0TX EP0RXTable 190: USB Endpoint Interrupt Clear register (USBEpIntClr - address 0xE009 0038) bit descriptionBit Symbol Value Description Reset value31:0 See0 No effect. 0USBEpIntClrbit allocationtable above1 Clears the corresponding bit in the Endpoint Interrupt Status register.Software is allowed to issue clear operation on multiple endpoints as well. Let us take anexample:Assume bits 5 and 10 of Endpoint Interrupt Status register are to be cleared. The softwarecan issue Clear operation by writing in Endpoint Interrupt Clear register (withcorresponding bit positions set to '1'). Then hardware will do the following:1. Clears CDFULL bit of Device Interrupt Status register.9397 750 XXXXX © Koninklijke Philips Electronics N.V. 2005. All rights reserved.User manual Rev. 01 — 15 August 2005 206