RM0090: Reference manual - STMicroelectronics

USB on-the-go full-speed (OTG_FS) RM0090
OTG_FS Host channel-x characteristics register (OTG_FS_HCCHARx)
(x = 0..7, where x = Channel_number)
Address offset: 0x500 + (Channel_number × 0x20)
Reset value: 0x0000 0000
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
CHENA
CHDIS
ODDFRM
DAD MCNT
1075/1416 Doc ID 018909 Rev 3
EPTYP
LSDEV
Reserved
EPDIR
EPNUM MPSIZ
rs rs rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw rw
Bit 31 CHENA: Channel enable
This field is set by the application and cleared by the OTG host.
0: Channel disabled
1: Channel enabled
Bit 30 CHDIS: Channel disable
The application sets this bit to stop transmitting/receiving data on a channel, even before the
transfer for that channel is complete. The application must wait for the Channel disabled
interrupt before treating the channel as disabled.
Bit 29 ODDFRM: Odd frame
This field is set (reset) by the application to indicate that the OTG host must perform a
transfer in an odd frame. This field is applicable for only periodic (isochronous and interrupt)
transactions.
0: Even frame
1: Odd frame
Bits 28:22 DAD: Device address
This field selects the specific device serving as the data source or sink.
Bits 21:20 MCNT: Multicount
This field indicates to the host the number of transactions that must be executed per frame
for this periodic endpoint. For non-periodic transfers, this field is not used
00: Reserved. This field yields undefined results
01: 1 transaction
10: 2 transactions per frame to be issued for this endpoint
11: 3 transactions per frame to be issued for this endpoint
Note: This field must be set to at least 01.
Bits 19:18 EPTYP: Endpoint type
Indicates the transfer type selected.
00: Control
01: Isochronous
10: Bulk
11: Interrupt
Bit 17 LSDEV: Low-speed device
This field is set by the application to indicate that this channel is communicating to a lowspeed
device.
Bit 16 Reserved, must be kept at reset value.