void ServiceUSB(void) {
__data BUFDESC *buf_desc_ptr;
if (UIRbits.UERRIF) {
UEIR = 0x00;
} else if (UIRbits.SOFIF) {
UIRbits.SOFIF = 0;
} else if (UIRbits.IDLEIF) {
UIRbits.IDLEIF = 0;
UCONbits.SUSPND = 1;
} else if (UIRbits.ACTVIF) {
UIRbits.ACTVIF = 0;
UCONbits.SUSPND = 0;
} else if (UIRbits.STALLIF) {
UIRbits.STALLIF = 0;
} else if (UIRbits.URSTIF) {
USB_curr_config = 0x00;
UIRbits.TRNIF = 0; // clear TRNIF four times to clear out the USTAT FIFO
UIRbits.TRNIF = 0;
UIRbits.TRNIF = 0;
UIRbits.TRNIF = 0;
/* disable all endpoints before resetting buffers */
UEP0 = 0x00;
disableUEP();
BD0O.bytecount = MAX_PACKET_SIZE;
BD0O.address = EP0_OUT_buffer; // EP0 OUT gets a buffer
BD0O.status = 0x88; // set UOWN bit (USB can write)
BD0I.address = EP0_IN_buffer; // EP0 IN gets a buffer
BD0I.status = 0x08; // clear UOWN bit (MCU can write)
BD1O.bytecount = MAX_PACKET_SIZE;
BD1O.address = EP0_OUT_buffer; // EP1 OUT gets a buffer
BD1O.status = 0x88; // set UOWN bit (USB can write)
BD1I.address = EP0_IN_buffer; // EP1 IN gets a buffer
BD1I.status = 0x08; // clear UOWN bit (MCU can write)
UADDR = 0x00; // set USB Address to 0
UIR = 0x00; // clear all the USB interrupt flags
UEP0 = ENDPT_CONTROL; // EP0 is a control pipe and requires an ACK
UEIE = 0xFF; // enable all error interrupts
USB_USWSTAT = DEFAULT_STATE;
USB_device_status = 0x01; // self powered, remote wakeup disabled
} else if (UIRbits.TRNIF) {
buf_desc_ptr = (__data void *)((BD_BASE)+(USTAT&0x7C)); // mask out bits 0, 1, and 7 of USTAT for offset into the buffer descriptor table
USB_buffer_desc.status = buf_desc_ptr->status;
USB_buffer_desc.bytecount = buf_desc_ptr->bytecount;
USB_buffer_desc.address = buf_desc_ptr->address;
USB_USTAT = USTAT; // save the USB status register
UIRbits.TRNIF = 0; // clear TRNIF interrupt flag
USB_error_flags = 0x00; // clear USB error flags
switch (USB_buffer_desc.status&0x3C) { // extract PID bits
case TOKEN_SETUP:
ProcessSetupToken();
break;
case TOKEN_IN:
ProcessInToken();
break;
case TOKEN_OUT:
ProcessOutToken();
}
if (USB_error_flags&0x01) { // if there was a Request Error...
BD0O.bytecount = MAX_PACKET_SIZE; // ...get ready to receive the next Setup token...
BD0I.status = 0x84;
BD0O.status = 0x84; // ...and issue a protocol stall on EP0
}
}
}
void ServiceUSB(void) {
BUFDESC *buf_desc_ptr;
if (UIRbits.UERRIF) {
UEIR = 0x00;
} else if (UIRbits.SOFIF) {
UIRbits.SOFIF = 0;
} else if (UIRbits.IDLEIF) {
UIRbits.IDLEIF = 0;
UCONbits.SUSPND = 1;
#ifdef SHOW_ENUM_STATUS
PORTB &= 0xE0;
PORTBbits.RB4 = 1;
#endif
} else if (UIRbits.ACTVIF) {
UIRbits.ACTVIF = 0;
UCONbits.SUSPND = 0;
#ifdef SHOW_ENUM_STATUS
PORTB &= 0xE0;
PORTB |= 0x01<<USB_USWSTAT;
#endif
} else if (UIRbits.STALLIF) {
UIRbits.STALLIF = 0;
} else if (UIRbits.URSTIF) {
USB_curr_config = 0x00;
UIRbits.TRNIF = 0; // clear TRNIF four times to clear out the USTAT FIFO
UIRbits.TRNIF = 0;
UIRbits.TRNIF = 0;
UIRbits.TRNIF = 0;
UEP0 = 0x00; // clear all EP control registers to disable all endpoints
UEP1 = 0x00;
UEP2 = 0x00;
UEP3 = 0x00;
UEP4 = 0x00;
UEP5 = 0x00;
UEP6 = 0x00;
UEP7 = 0x00;
UEP8 = 0x00;
UEP9 = 0x00;
UEP10 = 0x00;
UEP11 = 0x00;
UEP12 = 0x00;
UEP13 = 0x00;
UEP14 = 0x00;
UEP15 = 0x00;
BD0O.bytecount = MAX_PACKET_SIZE;
BD0O.address = EP0_OUT_buffer; // EP0 OUT gets a buffer
BD0O.status = 0x88; // set UOWN bit (USB can write)
BD0I.address = EP0_IN_buffer; // EP0 IN gets a buffer
BD0I.status = 0x08; // clear UOWN bit (MCU can write)
UADDR = 0x00; // set USB Address to 0
UIR = 0x00; // clear all the USB interrupt flags
UEP0 = ENDPT_CONTROL; // EP0 is a control pipe and requires an ACK
UEIE = 0xFF; // enable all error interrupts
USB_USWSTAT = DEFAULT_STATE;
USB_device_status = 0x01; // self powered, remote wakeup disabled
#ifdef SHOW_ENUM_STATUS
PORTB &= 0xE0;
PORTBbits.RB1 = 1; // set bit 1 of PORTB to indicate Powered state
#endif
} else if (UIRbits.TRNIF) {
buf_desc_ptr = (BUFDESC *)((unsigned char *)(&BD0O)+(USTAT&0x7C)); // mask out bits 0, 1, and 7 of USTAT for offset into the buffer descriptor table
USB_buffer_desc.status = buf_desc_ptr->status;
USB_buffer_desc.bytecount = buf_desc_ptr->bytecount;
USB_buffer_desc.address = buf_desc_ptr->address;
USB_USTAT = USTAT; // save the USB status register
UIRbits.TRNIF = 0; // clear TRNIF interrupt flag
#ifdef SHOW_ENUM_STATUS
switch (USB_USTAT&0x18) { // toggle bit 5, 6, or 7 of PORTB to reflect EP0, EP1, or EP2 activity
case EP0:
PORTB ^= 0x20;
break;
case EP1:
PORTB ^= 0x40;
break;
case EP2:
PORTB ^= 0x80;
}
#endif
USB_error_flags = 0x00; // clear USB error flags
switch (USB_buffer_desc.status&0x3C) { // extract PID bits
case TOKEN_SETUP:
ProcessSetupToken();
break;
case TOKEN_IN:
ProcessInToken();
break;
case TOKEN_OUT:
ProcessOutToken();
}
if (USB_error_flags&0x01) { // if there was a Request Error...
BD0O.bytecount = MAX_PACKET_SIZE; // ...get ready to receive the next Setup token...
BD0I.status = 0x84;
BD0O.status = 0x84; // ...and issue a protocol stall on EP0
}
}
}
