AN2131QC Cypress Semiconductor Corp, AN2131QC Datasheet - Page 144

• Manufacturer Part Number: AN2131QC
• Description: IC MCU 8051 8K RAM 24MHZ 80BQFP
• Manufacturer: Cypress Semiconductor Corp
• Series: EZ-USB®r

Specifications of AN2131QC

• Applications: USB Microcontroller
• Core Processor: 8051
• Program Memory Type: ROMless
• Controller Series: AN213x
• Ram Size: 8K x 8
• Interface: I²C, USB
• Number Of I /o: 24
• Voltage - Supply: 3 V ~ 3.6 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 80-QFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: 428-1307

7.3.12 Firmware Load
The USB endpoint zero protocol provides a mechanism for mixing vendor-specific
requests with the previously described standard device requests. Bits 6:5 of the bmRe-
quest field are set to 00 for a standard device request, and to 10 for a vendor request.
The EZ-USB core responds to two endpoint zero vendor requests, RAM Download and
RAM Upload. These requests are active in all modes (ReNum=0 or 1).
Because bit 7 of the first byte of the SETUP packet specifies direction, only one bRequest
value (0xA0) is required for the upload and download requests. These RAM load com-
mands are available to any USB device that uses the EZ-USB chip.
A host loader program typically writes 0x01 to the CPUCS register to put the 8051 into
RESET, loads all or part of the EZ-USB internal RAM with 8051 code, and finally reloads
the CPUCS register with 0 to take the 8051 out of RESET. The CPUCS register is the
only USB register that can be written using the Firmware Download command.
EZ-USB TRM v1.9
Byte
Byte
0
1
2
3
4
5
6
7
0
1
2
3
4
5
6
7
bmRequestType
bRequest
wValueL
wValueH
wIndexL
wIndexH
wLengthL
wLengthH
bmRequestType
bRequest
wValueL
wValueH
wIndexL
wIndexH
wLengthL
wLengthH
Field
Field
Table 7-21. Firmware Download
Table 7-22. Firmware Upload
AddrH
AddrH
AddrL Starting address
AddrL Starting address
Value
Value
LenH
LenH
0xA0 “Firmware Load”
LenL Number of bytes
0xC0 Vendor Request, IN
0xA0 “Firmware Load”
LenL Number of Bytes
0x40 Vendor Request, OUT
0x00
0x00
0x00
0x00
Chapter 7. EZ-USB CPU
Meaning
Meaning
None required
None Required
8051 Response
8051 Response
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