Core - Pin Configuration (A2)
Report Type: IN / OUT
Report Size: 19 Bytes
Acknowledged By: Command Acknowledgement
| Report ID |
Unlock Key |
Suspend Behaviour |
Interface ID |
Function ID |
Function Arguments |
| 01 00 0010 |
8 bytes |
ss r 00 o wp |
0000 iiii |
ffffffff |
7 bytes |
THIS COMMAND HAS THE POTENTIAL TO DESTROY THE DEVICE AND / OR CONNECTED CIRCUITRY, IE. BY SHORT-CIRCUITING TWO OUTPUTS TOGETHER.
Report ID
HID Report ID. Always 0x42.
The Pin Configuration report IDs all follow this encoding scheme:
| Bits |
Direction |
Meaning |
| 01 |
|
|
bb |
IN / OUT |
Bank number; 00 for A, 01 for B, 10 for C and 11 is reserved. |
pppp |
IN / OUT |
The pin’s index into the bank. |
For example, pin B0 is 01 0000, C9 is 10 1001, etc. Thus A2 is 00 0010. Undefined pins give invalid
report IDs and so will result in a Negative Command Acknowledgement response. No changes will be made in this instance.
Unlock Key
An 8-byte key that is compared against a previously stored value.
This mechanism prevents accidental in-circuit re-configuration of a pin, which could adversely affect
the device or connected circuit.
If the given key does not match the one stored against the configuration then the command will have no effect and a Negative
Command Acknowledgement will be returned.
For an IN Report this will be all zeroes.
Suspend Behaviour
The behaviour of the pin when the device enters Suspend.
| Bits |
Direction |
Meaning |
ss |
IN / OUT |
Suspend behaviour; 00 for unchanged, 01 to switch to input, 10 to output low, 11 to output high. |
r |
IN / OUT |
Remote Wake-Up; 0 to disable, 1 to wake from Suspend when a transition occurs on the pin. |
| 00 |
|
|
o |
IN / OUT |
Output type; 0 for push-pull, 1 for open-drain. |
wp |
IN / OUT |
Weak Pulls; 00 for none, 01 for pull-down, 10 for pull-up, 11 is reserved but will enable the pull-up. |
Interface ID
Out-of-range Interface IDs, ie. those not listed below, will cause a Negative Command Acknowledgement.
Any pin can be assigned to this interface.
GPIO
The pin is assigned to the GPIO function. Any pin can be assigned to this function.
| Function ID |
Pin Behaviour |
Interrupt Behaviour |
Flags |
Reserved |
000000dd |
0000 l o wp |
00000 p n m |
0000 iiii |
00000000 00000000 00000000 00000000 |
| Bits |
Direction |
Meaning |
| 000000 |
|
|
dd |
IN / OUT |
Pin direction; 00 for input, 01 for output, 10 and 11 are reserved but will default to input and output, respectively. |
| Bits |
Direction |
Meaning |
| 0000 |
|
|
l |
IN / OUT |
The initial value of the output latch after power-on. |
o |
IN / OUT |
Output type; 0 for push-pull, 1 for open-drain. |
wp |
IN / OUT |
Weak Pulls; 00 for none, 01 for pull-down, 10 for pull-up, 11 is reserved but will enable the pull-up. |
| Bits |
Direction |
Meaning |
| 00000 |
|
|
p |
IN / OUT |
Interrupt on positive edges if set to 1. |
n |
IN / OUT |
Interrupt on negative edges if set to 1. |
m |
IN / OUT |
Interrupt mode; 0 for one-shot, 1 for continuous. |
| Bits |
Direction |
Meaning |
| 0000 |
|
|
iiii |
IN / OUT |
An ID for the pin, in the range [0, 10]. This is useful for assigning application-specific weights to the pins, for example during parallel value outputs. |
It is not possible to assign the same ID to multiple pins - the pin assigned last ‘wins’. The default mapping is:
| A2 |
A3 |
A4 |
B0 |
B1 |
B2 |
B3 |
B4 |
B5 |
B7 |
C9 |
| 0 |
1 |
2 |
3 |
4 |
5 |
6 |
7 |
8 |
9 |
10 |
Any pin can be assigned to this interface.
Status Flags
The pin is assigned to the Status Flags function which provides information on the state of the USB cable, connector and protocol.
Any pin can be assigned to this function. Multiple pins can be assigned to this function, each with independent parameters.
Multiple flags can be combined together into a single output pin using either an AND or an OR operation. Flags can also be inverted
prior to the combining operation. This scheme provides a very flexible method of signalling USB state to connected circuitry.
For example, it is possible to have a pin indicating the condition of NOT attached to a dedicated charger AND the device can source a current of at least 100mA.
| Function ID |
Pin Behaviour |
Mask LSB |
Mask MSB |
Mask Inversion LSB |
Mask Inversion MSB |
Current LSB |
Current MSB |
0000100 m |
0000 l o wp |
h g f e d c b a |
0 s r q p k j i |
H G F E D C B A |
0 S R Q P K J I |
cccccccc |
000000 cc |
| Bits |
Direction |
Meaning |
| 0000100 |
|
|
m |
IN / OUT |
The flag mode; 0 to trigger on any flag in the mask (‘OR’), 1 to trigger on all flags (‘AND’). |
| Bits |
Direction |
Meaning |
| 0000 |
|
|
l |
IN / OUT |
The active-state; 0 for active-low, 1 for active-high. |
o |
IN / OUT |
Output type; 0 for push-pull, 1 for open-drain. |
wp |
IN / OUT |
Weak Pulls; 00 for none, 01 for pull-down, 10 for pull-up, 11 is reserved but will enable the pull-up. |
| Bits |
Direction |
Meaning |
a |
IN / OUT |
Attached to a device (ie. a Source (Host) will be on the other end of the cable). |
b |
IN / OUT |
Attached as a Debug (Sink) Accessory. |
c |
IN / OUT |
Attached to an Audio (Sink / Source) Accessory - THE ELECTRICAL SPECIFICATIONS FOR AUDIO ACCESSORIES ARE NOT SUPPORTED AND WILL DAMAGE THE DEVICE; THIS FLAG IS FOR INFORMATION ONLY. |
d |
IN / OUT |
The cable is an active cable. |
e |
IN / OUT |
The VBUS (+5V) voltage is within USB specifications. |
f |
IN / OUT |
The voltage on the CC pins is within USB specifications. |
g |
IN / OUT |
The CC1 pin (USB connector pin A5) is connected. |
h |
IN / OUT |
The CC2 pin (USB connector pin B5) is connected. |
i |
IN / OUT |
No faults have occurred when examining the CC pin(s). |
j |
IN / OUT |
The D+ / D- lines were checked for short on power-up. |
k |
IN / OUT |
The D+ / D- lines were shorted on power-up, a crude indication of being connected to a dedicated charger. |
p |
IN / OUT |
Source has suspended the device. |
q |
IN / OUT |
USB enumeration has completed. |
r |
IN / OUT |
USB protocol error has occurred (one or more endpoints are in the HALTED state). |
s |
IN / OUT |
Source device’s current capability is at least (cc cccccccc * 2)mA. |
| Bits |
Direction |
Meaning |
A |
IN / OUT |
Value to be XOR’d with flag a; if 1 then flag a will be inverted before evaluation (ie. 1 if a device is NOT attached and 0 otherwise). |
| … |
IN / OUT |
… |
S |
IN / OUT |
Value to be XOR’d with flag s; if 1 then flag s will be inverted before evaluation (ie. 1 if the Source CANNOT provide the requested current, 0 if it can). |
| Bits |
Direction |
Meaning |
cccccccc |
IN / OUT |
Least significant bits of a value representing a current, in units of 2mA. This is used during evaluation of the s flag. |
| 000000 |
IN / OUT |
Reserved for future expansion; set to all zeroes. |
cc |
IN / OUT |
The two most significant bits of the current. |
Only pins B2 and B3 can be assigned to this interface, and they cannot be configured individually. If the I2C module has been enabled
then any configuration of the B2 and B3 pins is overridden.
Any pin can be assigned to this interface.
Clock
The pin is assigned to the SPI Clock function. Any pin can be assigned to this function.
| Function ID |
Pin Behaviour |
Reserved |
| 00000001 |
0000 l o wp |
6 bytes (should be all zeroes) |
| Bits |
Direction |
Meaning |
| 0000 |
|
|
l |
IN / OUT |
The latch state when no slaves are selected; 0 for low, 1 for high. |
o |
IN / OUT |
Output type; 0 for push-pull, 1 for open-drain. |
wp |
IN / OUT |
Weak Pulls; 00 for none, 01 for pull-down, 10 for pull-up, 11 is reserved but will enable the pull-up. |
MISO (Master-In, Slave-Out)
The pin is assigned to the SPI MISO function. Any pin can be assigned to this function.
| Function ID |
Pin Behaviour |
Reserved |
| 00000010 |
000000 wp |
6 bytes (should be all zeroes) |
| Bits |
Direction |
Meaning |
| 000000 |
|
|
wp |
IN / OUT |
Weak Pulls; 00 for none, 01 for pull-down, 10 for pull-up, 11 is reserved but will enable the pull-up. |
MOSI (Master-Out, Slave-In)
The pin is assigned to the SPI MOSI function. Any pin can be assigned to this function.
| Function ID |
Pin Behaviour |
Reserved |
| 00000011 |
0000 l o wp |
6 bytes (should be all zeroes) |
| Bits |
Direction |
Meaning |
| 0000 |
|
|
l |
IN / OUT |
The latch state when no slaves are selected; 0 for low, 1 for high. |
o |
IN / OUT |
Output type; 0 for push-pull, 1 for open-drain. |
wp |
IN / OUT |
Weak Pulls; 00 for none, 01 for pull-down, 10 for pull-up, 11 is reserved but will enable the pull-up. |
Frame Select
The pin is assigned to the SPI Frame Select function. Any pin can be assigned to this function.
| Function ID |
Pin Behaviour |
Reserved |
| 00000100 |
0000 l o wp |
6 bytes (should be all zeroes) |
| Bits |
Direction |
Meaning |
| 0000 |
|
|
l |
IN / OUT |
The latch state when no slaves are selected; 0 for low, 1 for high. |
o |
IN / OUT |
Output type; 0 for push-pull, 1 for open-drain. |
wp |
IN / OUT |
Weak Pulls; 00 for none, 01 for pull-down, 10 for pull-up, 11 is reserved but will enable the pull-up. |
Slave Select
The pin is assigned to the SPI Slave Select function. Any pin can be assigned to this function.
| Function ID |
Pin Behaviour |
Reserved |
00001 nnn |
0000 l o wp |
6 bytes (should be all zeroes) |
| Bits |
Direction |
Meaning |
| 00001 |
|
|
nnn |
IN / OUT |
Slave number, in the range [0, 7]. |
| Bits |
Direction |
Meaning |
| 0000 |
|
|
l |
IN / OUT |
The active-state; 0 for active-low, 1 for active-high. |
o |
IN / OUT |
Output type; 0 for push-pull, 1 for open-drain. |
wp |
IN / OUT |
Weak Pulls; 00 for none, 01 for pull-down, 10 for pull-up, 11 is reserved but will enable the pull-up. |
THIS COMMAND HAS THE POTENTIAL TO DESTROY THE DEVICE AND / OR CONNECTED CIRCUITRY, IE. BY SHORT-CIRCUITING TWO OUTPUTS TOGETHER.
