Philips UDA1325

1999 May 10 33

Philips Semiconductors Preliminary speciﬁcation

Universal Serial Bus (USB) CODEC UDA1325

Table 26 Error codes

Table 27

ERROR

CODE RESULT

0000 no error

0001 PID encoding error; bits 7 to 4 in the PID

token are not the inversion of bits 3 to 0

0010 PID unknown; PID encoding is valid, but PID

does not exist

0011 unexpected packet; packet is not of the type

expected (token, data or acknowledge), or

SETUP token received on non-control

endpoint

0100 token CRC error

0101 data CRC error

0110 time out error

0111 babble error

1000 unexpected end-of-packet

1001 sent or received NAK

1010 sent stall, a token was received, but the

endpoint was stalled

1011 overﬂow error, the received data packet was

larger then the buffer size of the selected

endpoint

1100 sent empty packet (ISO only)

1101 bitstuff error

1110 error in sync

1111 wrong data PID

BIT DESCRIPTION

Data receive/transmit a ‘1’ indicates data has

been received or

transmitted successfully

Error code see Table 26

Setup packet a ‘1’ indicates the last

received packet had a

SETUP token (this will

always read ‘0’ for IN

buffers)

Data 0/1 packet a ‘1’ indicates the last

received packet had a

DATA 1 PID

Previous status not read a ‘1’ indicates a second

event occurred before the

previous status was read

SET ENDPOINT STATUS

Command: 40h + endpoint index.

Data: write 1 byte.

This command is used to stall or unstall an endpoint. Only

the least significant bit has a meaning. When the stalled bit

is equal to 1, the endpoint is stalled, when equal to 0, the

endpoint is unstalled. There is one command for every

endpoint.

A stalled control endpoint is automatically unstalled when

it receives a SETUP token, regardless of the contents of

the packet. If the endpoint should stay in stalled state, the

microcontroller should restall it.

When a stalled endpoint is unstalled, it is also re-initialized.

This means that its buffer is flushed and the next DATA

PID that will be sent or expected (depending on the

direction of the endpoint) is DATA0.

READ BUFFER

Command: F0h.

Data: read n bytes (max. 10).

The read buffer command is followed by a number of data

reads, which returns the contents of the selected endpoint

data buffer. After each read, the internal buffer pointer is

incremented by 1.

The buffer pointer is not reset to the buffer start by the read

buffer command. This means that reading a buffer can be

interrupted by any other command (except for select

endpoint).

Stalled

Reserved

01234567

XXX XXX Power On Value