Team2890/allwpilib
4
0
Fork 0
mirror of https://github.com/wpilibsuite/allwpilib synced 2026-06-19 00:41:43 +00:00
Code Issues Packages Projects Releases Wiki Activity

[xrp] Add Support for Encoder Period on XRP (#6795)

Browse Source 
The XRP firmware has been updated to provide the
encoder period along with the encoder count.

This change allows WPILIB to use the encoder period
data from the XRP so that the GetRate function can
be used to determine the motor speed.
This commit is contained in:
beardedone55
2024-07-02 15:29:52 -05:00
committed by GitHub
parent 1ccd8d14f0
commit 7366a03fc9
2 changed files with 40 additions and 7 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
simulation/halsim_xrp/README.md
View File

@@ -111,10 +111,12 @@ IDs:
#### Encoder
| Order | Data Type | Description |
|-------|-----------|-------------|
| 0 | _uint8_t_ | ID |
| 1 | _int32_t_ | Value |
| Order | Data Type | Description |
|-------|------------|--------------------|
| 0 | _uint8_t_ | ID |
| 1 | _int32_t_ | Count |
| 2 | _uint32_t_ | Period Numerator |
| 3 | _uint32_t_ | Period Denominator |
IDs:
| ID | Description |

37
simulation/halsim_xrp/src/main/native/cpp/XRP.cpp
View File

@@ -342,13 +342,17 @@ void XRP::ReadDIOTag(std::span<const uint8_t> packet) {
void XRP::ReadEncoderTag(std::span<const uint8_t> packet) {
if (packet.size() < 7) {
return; // size(1) + tag(1) + id(1) + value(4)
return; // size(1) + tag(1) + id(1) + count(4)
}
// size(1) + tag(1) + id(1) + count(4) + period_numerator(4) +
// period_denominator(4)
bool containsPeriod = packet.size() >= 15;
uint8_t encoderId = packet[2];
packet = packet.subspan(3); // Skip past the size and tag and ID
int32_t value =
int32_t count =
static_cast<int32_t>(wpi::support::endian::read32be(&packet[0]));
// Look up the registered encoders
@@ -361,7 +365,34 @@ void XRP::ReadEncoderTag(std::span<const uint8_t> packet) {
wpi::json encJson;
encJson["type"] = "Encoder";
encJson["device"] = std::to_string(wpilibEncoderChannel);
encJson["data"] = {{">count", value}};
encJson["data"] = {{">count", count}};
if (containsPeriod) {
// Older versions of XRP firmware do not provide Encoder Period.
// Only calculate period if the Encoder packet contains the period data.
// The period is a fraction consisting of two integers: a numerator and
// denominator. The least significant bit of the numerator specifies the
// direction: 1 -> forward, 0 -> reverse. The direction bit must be removed
// to calculate the magnitude of the period.
size_t i = sizeof(count);
uint32_t period_numerator =
static_cast<uint32_t>(wpi::support::endian::read32be(&packet[i]));
i += sizeof(period_numerator);
uint32_t period_denominator =
static_cast<uint32_t>(wpi::support::endian::read32be(&packet[i]));
double period =
static_cast<double>(period_numerator >> 1) / period_denominator;
// If direction is not forward, return negative value for period.
if (!(period_numerator & 1))
period = -period;
encJson["data"].push_back({wpi::json(">period"), wpi::json(period)});
}
m_wpilib_update_func(encJson);
}