M68HC08 datasheet(192/332 Pages) FREESCALE

192 / 332 page

Universal Serial Bus Module (USB)

Technical Data

MC68HC908JB16 — Rev. 1.1

192

Universal Serial Bus Module (USB)

Freescale Semiconductor

STALL2 — Endpoint 2 Force Stall Bit

This read/write bit causes endpoint 2 to return a STALL handshake

when polled by either an IN or OUT token by the USB host controller.

Reset clears this bit.

1 = Send STALL handshake

0 = Default

TX2E — Endpoint 2 Transmit Enable

This read/write bit enables a transmit to occur when the USB host

controller sends an IN token to endpoint 2. The appropriate endpoint

enable bit, ENABLE2 bit in the UCR3 register, also should be set.

Software should set the TX2E bit when data is ready to be

transmitted. It must be cleared by software when no more data needs

to be transmitted.

If this bit is 0 or the TXD2F is set, the USB will respond with a NAK

handshake to any endpoint 2 directed IN tokens. Reset clears this bit.

1 = Data is ready to be sent

0 = Data is not ready. Respond with NAK

RX2E — Endpoint 2 Receive Enable

This read/write bit enables a receive to occur when the USB host

controller sends an OUT token to endpoint 2. Software should set this

bit when data is ready to be received. It must be cleared by software

when data cannot be received.

If this bit is 0 or the RXD2F is set, the USB will respond with a NAK

handshake to any endpoint 2 OUT tokens. Reset clears this bit.

1 = Data is ready to be received

0 = Not ready for data. Respond with NAK

TP2SIZ3–TP2SIZ0 — Endpoint 2 Transmit Data Packet Size

These read/write bits store the number of transmit data bytes for the

next IN token request for endpoint 2. These bits are cleared by reset.

M68HC08 Datasheet(PDF) 192 Page - Freescale Semiconductor, Inc