upd78f0730 Renesas Electronics Corporation., upd78f0730 Datasheet - Page 283

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

Next, the procedure of a SETUP transaction that uses IN/OUT tokens is explained below.
(a) When IN token is used (except a request automatically executed by hardware)
(b) When OUT token is used (except a request automatically executed by hardware)
FW should be used to clear the PROT bit of the UF0IS1 register to 0 after receiving the CPUDEC interrupt
and before reading data from the UF0E0ST register. Next, perform processing in accordance with the
request and, if it is necessary to return data by an IN token, write data to the UF0E0W register. Confirm
that the PROT bit of the UF0IS1 register is 0 after writing has been completed, and set the E0DED bit of
the UF0DEND register to 1. The hardware sends out data at the first IN token after the EP0NKW bit has
been set to 1. If the PROT bit of the UF0IS1 register is 1, it indicates that a SETUP transaction has
occurred again before completion of control transfer. In this case, clear the PROT bit of the UF0IS1
register to 0 by clearing the PROTC bit of the UF0IC1 register to 0, and then read data from the UF0E0ST
register again. A request received later can be read.
FW should be used to clear the PROT bit of the UF0IS1 register after receiving the CPUDEC interrupt and
before reading data from the UF0E0ST register. Confirm that the PROT bit of the UF0IS1 register is 0
before reading data from the UF0E0R register. If the PROT bit is 1, it means that invalid data is retained.
Clear the FIFO by FW (the EP0NKR bit is automatically cleared to 0). If the PROT bit of the UF0IS1
register is 0, read the data of the UF0E0L register and read as many data from the UF0E0R register as set.
When reading data from the UF0E0R register has been completed (when the counter of the UF0E0R
register has been cleared to 0), the hardware automatically clears the EP0NKR bit to 0.
CHAPTER 12 USB FUNCTION CONTROLLER (USBF)
Preliminary User’s Manual U19014EJ1V0UD
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