upd78f0730 Renesas Electronics Corporation., upd78f0730 Datasheet - Page 338

• Manufacturer Part Number: upd78f0730
• Description: 8-bit Single-chip Microcontroller
• Manufacturer: Renesas Electronics Corporation.

338
(3) UF0 EP1 status register L (UF0E1SL)
UF0E1SL
Bit position
This register stores the value that is to be returned in response to the GET_STATUS Endpoint1 request.
This register can be read or written in 8-bit units. Note, however, that data can be written to this register only
when the EP0NKA bit is set to 1.
If an error occurs in Endpoint1, the E1HALT bit is set to 1. A write access to this register is ignored while a
USB-side access to Endpoint1 is being received.
The hardware automatically transmits the contents of this register to the host when it has received the
GET_STATUS Endpoint1 request. If Endpoint1 has stalled, the UF0BI1 register is cleared and the BKI1NK bit
is cleared to 0.
Because writing this register is always masked when transfer to Endpoint1, rather than control transfer, is
executed, be sure to check this register to see if data has been correctly written to it.
Caution To rewrite this register, set the EP0NKA bit to 1 before reading the register contents, and
0
7
0
rewrite the register contents after confirming that the bit has been set, in order to prevent
conflict between a read access and a write access.
E1HALT
Bit name
6
0
CHAPTER 12 USB FUNCTION CONTROLLER (USBF)
This bit indicates the status of Endpoint1.
This bit is set to 1 by hardware when the SET_FEATURE Endpoint1 request has been
received. It is cleared to 0 by hardware when the CLEAR_FEATURE Endpoint1 request,
SET_CONFIGURATION request, or the SET_INTERFACE request for the Interface to
which Endpoint1 is linked has correctly been received. DATA PID is initialized to DATA0.
5
0
1: Stalled
0: Not stalled
Preliminary User’s Manual U19014EJ1V0UD
4
0
3
0
2
0
Function
1
0
E1HALT
0
Address
FF9DH
After reset
00H