Semiconductor Group
6-66
1999-04-01
On-Chip Peripheral Components
C541U
6.4.7.3
Endpoint Registers
Each of the five endpoints has its own endpoint register set which contains the following registers
(n=0-4) :
– EPBCn
Endpoint n Buffer Control Register
– EPBSn
Endpoint n Buffer Status Register
– EPIERn Endpoint n Interrupt Enable Register
– EPIRRn Endpoint n Interrupt Request Register
– EPBAn
Endpoint n Base Address Register
– EPLENn Endpoint n Buffer Length Register
The endpoint buffer control registers control the endpoint specific operations.
Endpoint 1 Buffer Control RegisterEPBCn, n=0-4 (Address C1H)
Reset Value : 00H
Bit
Function
STALLn
Endpoint stall
Bit STALL can be set to indicate that the endpoint is stalled.
If STALL=0, the endpoint n is active.
If STALL=1, the endpoint n is stalled.
Note : If the stall bit for endpoint 0 (STALL0) is set, the next incoming setup token
will automatically clear it.
GEPIEn
Global endpoint interrupt enable
Bit GEPIEn enables or disables the generation of the global endpoint interrupt n
based on the endpoint specific interrupt request bits in register EPIRn.
If GEPIE=0, the USB endpoint n interrupt is disabled.
If GEPIE=1, the USB endpoint n interrupt is enabled.
SOFDEn
Start of frame done enable
If bit SOFDE is set, the current CPU buffer in USB memory is automatically tagged
full (data flow from the CPU to the USB) or empty (data flow from the USB to the
CPU) on each detection of a start of frame on the USB (auto-done).
If SOFDE=0, no action on SOF.
If SOFDE=1, the automatical generation of DONE on SOF is enabled.
0
Reserved for future use. For compatiblity, these bits have to be ignored in all read
accesses and written with zero in all write accesses.
MSB
LSB
EPBCn
STALLn
0
0
GEPIEn SOFDEn INCEn
0
DBMn
7
6
5
4
3
2
1
0
Bit No.
rw
r
r
rw
rw
rw
r
rw
C1H
Summary of Contents for C541U
Page 1: ... 8 LW 026 0LFURFRQWUROOHU 8VHU V 0DQXDO http www siem ens d Sem iconductor ...
Page 7: ......
Page 21: ...Semiconductor Group 2 6 1997 10 01 Fundamental Structure C541U ...
Page 37: ...Semiconductor Group 4 6 1997 10 01 External Bus Interface C541U ...
Page 133: ...Semiconductor Group 6 88 1999 04 01 On Chip Peripheral Components C541U ...
Page 163: ...Semiconductor Group 8 8 1997 10 01 Fail Safe Mechanisms C541U ...
Page 185: ...Semiconductor Group 10 14 1997 10 01 OTP Memory Operation C541U ...