C541U_99 Datasheet, PDF (148/192 Pages) Siemens Semiconductor Group – 8-BIT CMOS MICROCONTROLLER

Interrupt System
C541U
The global endpoint interrupt request register GEPIRn (n=0-4) contaíns one flag for each endpoint
which indicates whether one or more of the seven endpoint specific interrupt requests has become
active. If a request flag in GEPIR is set, it is automatically cleared after a read operation of the
GEPIR register.
USB Global Endpoint Interrupt Request Register GEPIR (Address D6H) Reset Value : 00H
Bit No. MSB
LSB
7
6
5
4
3
2
1
0
D6H DRVI
0
r
r
0
EPI4 EPI3 EPI2 EPI1 EPI0 GEPIR
r
r
r
r
r
r
Bit
EPI4
EPI3
EPI2
EPI1
EPI0
Function
Endpoint 4 interrupt request flag
If EPI4 is set, an endpoint 4 interrupt request is pending.
Endpoint 3 interrupt request flag
If EPI3 is set, an endpoint 3 interrupt request is pending.
Endpoint 2 interrupt request flag
If EPI2 is set, an endpoint 2 interrupt request is pending.
Endpoint 1 interrupt request flag
If EPI1 is set, an endpoint 1 interrupt request is pending.
Endpoint 0 interrupt request flag
If EPI0 is set, an endpoint 0 interrupt request is pending.
Semiconductor Group
7-15
1997-10-01