AT80SND1C-ROTIL datasheet(86/210 Pages) ATMEL

86 / 210 page

AT8xC51SND1C

4109E–8051–06/03

•

Endpoint FIFO reset

Before using an endpoint, its FIFO should be reset. This action resets the FIFO

pointer to its original value, resets the Byte counter of the endpoint (UBYCTX regis-

ter), and resets the data toggle bit (DTGL bit in UEPCONX).

The reset of an endpoint FIFO is performed by setting to 1 and resetting to 0 the

corresponding bit in the UEPRST register.

For example, in order to reset the Endpoint number 2 FIFO, write 0000 0100b then

0000 0000b in the UEPRST register.

Note that the endpoint reset doesn’t reset the bank number for ping-pong endpoints.

Read/Write Data FIFO

Read Data FIFO

The read access for each OUT endpoint is performed using the UEPDATX register.

After a new valid packet has been received on an Endpoint, the data are stored into the

FIFO and the Byte counter of the endpoint is updated (UBYCTX registers). The firmware

has to store the endpoint Byte counter before any access to the endpoint FIFO. The

Byte counter is not updated when reading the FIFO.

To read data from an endpoint, select the correct endpoint number in UEPNUM and

read the UEPDATX register. This action automatically decreases the corresponding

address vector, and the next data is then available in the UEPDATX register.

Write Data FIFO

The write access for each IN endpoint is performed using the UEPDATX register.

To write a Byte into an IN endpoint FIFO, select the correct endpoint number in UEP-

NUM and write into the UEPDATX register. The corresponding address vector is

automatically increased, and another write can be carried out.

Warning 1: The Byte counter is not updated.

Warning 2: Do not write more Bytes than supported by the corresponding endpoint.

FIFO Mapping

Figure 61. Endpoint FIFO Configuration

UEPNUM

Endpoint 0

Endpoint 2

UEPSTA0

UEPCON0

UEPDAT0

UEPSTA2

UEPCON2

UEPDAT2

SFR Registers

UEPSTAX

UEPCONX

UEPDATX

UBYCT0

UBYCT2

UBYCTX

AT80SND1C-ROTIL Datenblatt(PDF) 86 Page - ATMEL Corporation

AT80SND1C-ROTIL Datenblatt(HTML) 86 Page - ATMEL Corporation

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datenblatt Download

Link URL