CY7C68300 CYPRESS [Cypress Semiconductor], CY7C68300 Datasheet - Page 13

• Manufacturer Part Number: CY7C68300
• Manufacturer: CYPRESS [Cypress Semiconductor]

5.1.2.2 Mfg_read
This USB request returns a “snapshot in time” of select EZ-USB AT2 input pins. The input pin states are bit-wise mapped to the
ATAPI data associated with this request. EZ-USB AT2 input pins not directly associated with USB operation can be sampled at
any time during Manufacturing Test Mode operation. See the following table for an explanation of the mfg_read data format. The
data length shall always be eight bytes.
Table 5-5. Mfg_read Data Format
5.2
In Normal Operation Mode, the chip behaves as a USB 2.0 to ATA/ATAPI bridge. This includes all typical USB device states
(powered, configured, etc.). The USB descriptors are returned according to the values stored in the external EEPROM. An
external EEPROM is required for Mass Storage Class Bulk-Only Transport compliance, since a unique serial number is required
for each device. Also, Cypress requires customers to use their own Vendor and Product IDs for final products.
5.3
The contents of the 256-byte (2048-bit) two-wire serial EEPROM are arranged as follows. The column labeled “Required
Contents” contains the values that must be used for proper operation of the EZ-USB AT2. The column labeled “Suggested
Contents” contains suggested values for the bytes that are defined by the manufacturer. Some values, such as the Vendor ID
and device and device serial number, must be customized to meet USB compliance. See subsection 5.1 for details on how to
use vendor-specific ATAPI commands to read and program the EEPROM. The serial EEPROM must be hard-wired to address
0x04. This means that A0 and A1 of the serial EEPROM must be tied to ground and that A2 must be tied to 3.3V.
Document #: 38-08011 Rev. *B
Byte
0
0
0
0
1
1
1
1
1
1
2
3
4
5
6
7
Normal Operation Mode
EEPROM Organization
Bit(s)
5:1
2:0
7:0
7:0
7:0
7:0
7:0
7:0
0
6
7
3
4
5
6
7
DD[7:0]
INTRQ
Reserved. This data should be ignored.
VBUS_PWR_VALID
ARESET# (output value only)
Reserved. This data should be ignored.
IORDY
DMARQ
ATA_EN
Reserved. This data should be ignored.
DD[15:0] Tri-state
DD[15:8]
Reserved. This data should be ignored.
Reserved. This data should be ignored.
Reserved. This data should be ignored.
Reserved. This data should be ignored.
Test/Three-state Control Function
CY7C68300
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