Datasheet

 2014 Microchip Technology Inc. DS20005292A-page 29
MCP2221
TABLE 3-6: RESPONSE STRUCTURE – READ GP SETTINGS SUB-COMMAND
Byte
Index
Function Description Value Effect
0 0xB0 Read Flash Data – command code echo
1 0x00 Command completed successfully
2 Structure length
3Don’t
care
4 GP0 Power-up Settings
Bit 7-5: Don’t
care
Bit 4: GPIO Output value When GP0 is set as an output GPIO, this value will be present
at the GP0 pin at Power-up/Reset.
Bit 3: GPIO Direction (Input/Out-
put) – Works only when GP0 is set
for GPIO operation
1 GPIO Input mode
0 GPIO Output mode
Bit 2-0: GP0 Designation 111-011 Don’t care
010 Alternate function 1 (LED UART RX)
001 Dedicated function operation (SSPND)
000 GPIO operation
5 GP1 Power-up Settings
Bits7-5: Don’t
care
Bit 4: GPIO Output value When GP1 is set as an output GPIO, this value will be present
at the GP1 pin at Power-up/Reset.
Bit 3: GPIO Direction (Input/Out-
put) – Works only when GP0 is set
for GPIO operation
1 GPIO Input mode
0 GPIO Output mode
Bit 2-0: GP1 Designation 111-101 Don’t care
001 Dedicated function operation (Clock Output)
100 Alternate function 3 (Interrupt Detection)
011 Alternate function 2 (LED UART TX)
010 Alternate function 1 (ADC 1)
000 GPIO operation
6 GP2 Power-up Settings
Bits7-5: Don’t
care
Bit 4: GPIO Output value When GP2 is set as an output GPIO, this value will be present
at the GP2 pin at Power-up/Reset.
Bit 3: GPIO Direction (Input/Out-
put). Works only when GP2 is set
for GPIO operation
1 GPIO Input mode
0 GPIO Output mode
Bit 2-0: GP1 Designation 111-100 Don’t care
011 Alternate function 2 (DAC1)
010 Alternate function 1 (ADC2)
001 Dedicated function operation (USB)
000 GPIO operation