ST72651AR6 STMicroelectronics, ST72651AR6 Datasheet - Page 74

• Manufacturer Part Number: ST72651AR6
• Description: LOW-POWER, FULL-SPEED USB 8-BIT MCU WITH 32K FLASH, 5K RAM, FLASH CARD I/F, TIMER, PWM, ADC, I2C, SPI
• Manufacturer: STMicroelectronics

Specifications of ST72651AR6

• Dual Supply Management: analog voltage detector on the USB power line to enable smart power switching from USB power to battery (on E suffix devices).
• Programmable Internal Voltage Regulator For Memory Cards (2.8v To 3.5v) Supplying: Flash Card I/O lines (voltage shifting)
• 5 Usb Endpoints: 1 control endpoint
• Dtc (data Transfer Coprocessor): Universal Serial/Parallel communications interface, with software plug-ins for current and future protocol standards

ST72651AR6
USB INTERFACE (Cont’d)
Bit 2= DTOG_TX Data Toggle, for transmission
transfers.
This bit contains the required value of the toggle
bit (0=DATA0, 1=DATA1) for the next data packet.
DTOG_TX and DTOG_RX are normally updated
by hardware, on receipt of a relevant PID. They
can be also written by the user, both for testing
purposes and to force a specific (DATA0 or
DATA1) token.
Bits 1:0 = STAT_TX [1:0] Status bits, for transmis-
sion transfers.
These bits contain the information about the end-
point status, which is listed below
Table 25. Transmission Status Encoding
These bits are written by software, but hardware
sets the STAT_TX bits to NAK when a correct
transfer (CTR=1) addressed to this endpoint has
occurred. This allows software to prepare the next
set of data to be transmitted.
Note: These bits are write protected in upload
mode (MOD[1:0] =01b in the EP2RXR register)
RECEPTION COUNTER REGISTER (CNT0RXR,
CNT1RXR)
Read/Write
Reset Value: 0000 0000 (00h)
This register contains the allocated buffer size for
endpoint 0 or 1 reception, setting the maximum
number of bytes the related endpoint can receive
with the next OUT (or SETUP for Endpoint 0)
transaction. At the end of a reception, the value of
this register is the max size decremented by the
number of bytes received (to determine the
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1
STAT_TX1 STAT_TX0
7
0
0
0
1
1
0
0
0
1
0
1
CNT4 CNT3 CNT2 CNT1 CNT0
DISABLED: transmission
transfers cannot be executed.
STALL: the endpoint is stalled
and all transmission requests
result in a STALL handshake.
NAK: the endpoint is naked
and all transmission requests
result in a NAK handshake.
VALID: this endpoint is ena-
bled for transmission.
Meaning
Doc ID 7215 Rev 4
0
number of bytes received, the software must sub-
tract the content of this register from the allocated
buffer size).
RECEPTION COUNTER REGISTER (CNT2RXR)
Read/Write
Reset Value: 0000 0000 (00h)
This register contains the allocated buffer size for
endpoint 2 reception, setting the maximum
number of bytes the related endpoint can receive
with the next OUT transaction. At the end of a re-
ception, the value of this register is the maximum
size decremented by the number of bytes received
(to determine the number of bytes received, the
software must subtract the content of this register
from the allocated buffer size).
TRANSMISSION COUNTER REGISTER
(CNT0TXR, CNT1TXR)
Read/Write
Reset Value 0000 0000 (00h)
This register contains the number of bytes to be
transmitted by Endpoint 0 or 1 at the next IN token
addressed to it.
TRANSMISSION COUNTER REGISTER
(CNT2TXR)
Read/Write
Reset Value 0000 0000 (00h)
This register contains the number of bytes to be
transmitted by Endpoint 2 at the next IN token ad-
dressed to it.
7
0
7
0
7
0
CNT6 CNT5 CNT4 CNT3 CNT2 CNT CNT0
CNT6 CNT5 CNT4 CNT3 CNT2 CNT1 CNT0
0
0
CNT4 CNT3 CNT2 CNT1 CNT0
0
0
0