Datasheet

2011 Microchip Technology Inc. DS22288A-page 29
MCP2210
3.1.8 GET USB KEY PARAMETERS
3.1.8.1 Responses
FIGURE 3-8: GET USB KEY PARAMETERS LOGIC FLOW
TABLE 3-21: COMMAND STRUCTURE
Byte
Index
Meaning
00x61 Get NVRAM Settings – command code
10x30 Get USB Key Parameters – sub-command code
20x00 Reserved
3-63 0x00Reserved
TABLE 3-22: RESPONSE 1 STRUCTURE
Byte
Index
Meaning
0 0x61 – Get NVRAM Settings – echos back the given command code
1 0x00 – Command Completed Successfully
2 0x30 – Sub-command Echoed Back for Get USB Key Parameters code
3-11 Don’t care
12 VID low byte
13 VID high byte
14 PID low byte
15 PID high byte
16-28 Don’t care
29 Chip Power Option (as per USB specs – Chapter 9)
Bit 7 – Host Powered
Bit 6 – Self Powered
Bit 5 – Remote Wake-up Capable
Bit 4 – Don’t Care
Bit 3 – Don’t Care
Bit 2 – Don’t Care
Bit 1 – Don’t Care
Bit 0 – Don’t Care
30 Requested Current Amount from USB Host (quanta of 2 mA)
Example
: For 100 mA this byte index will have a value of 50 (in decimal) or 0x32.
31-63 Don’t Care
Get NVRAM USB
Key Parameters
Response 1
NVRAM USB
Key Parameters
Retrieved