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CDC device tests with MCP2221

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This commit is contained in:
Kai Morich 2025-04-17 22:49:38 +02:00
parent 52042f8c3e
commit 06faad5622
4 changed files with 121 additions and 126 deletions
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6
.idea/AndroidProjectSystem.xml generated Normal file
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@ -0,0 +1,6 @@
<?xml version="1.0" encoding="UTF-8"?>
<project version="4">
<component name="AndroidProjectSystem">
<option name="providerId" value="com.android.tools.idea.GradleProjectSystem" />
</component>
</project>

2
usbSerialForAndroid/coverage.gradle
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@ -8,7 +8,7 @@ android {
// Used as fallback in usbSerialExample/build.gradle -> missingDimensionStrategy, but not for coverage report // Used as fallback in usbSerialExample/build.gradle -> missingDimensionStrategy, but not for coverage report
dimension 'device' dimension 'device'
} }
arduino { mcp2221 {
dimension 'device' dimension 'device'
testInstrumentationRunnerArguments = ['test_device_driver': 'CdcAcm'] testInstrumentationRunnerArguments = ['test_device_driver': 'CdcAcm']
} }

237
usbSerialForAndroid/src/androidTest/java/com/hoho/android/usbserial/DeviceTest.java
View File

@ -645,7 +645,13 @@ public class DeviceTest {
Thread.sleep(10); Thread.sleep(10);
usb.write(new byte[]{(byte) 0xff}); usb.write(new byte[]{(byte) 0xff});
data = telnet.read(2); data = telnet.read(2);
assertThat("19000/7N1", data, equalTo(new byte[]{(byte) 0x80, (byte) 0xff})); if(usb.serialDriver instanceof CdcAcmSerialDriver) {
// not supported by MCP2221, other CDC devices might support it
assertThat("19000/7N1", data, equalTo(new byte[]{(byte) 0x00, (byte) 0xff}));
return;
} else {
assertThat("19000/7N1", data, equalTo(new byte[]{(byte) 0x80, (byte) 0xff}));
}
} catch (UnsupportedOperationException e) { } catch (UnsupportedOperationException e) {
if(!usb.isCp21xxRestrictedPort) if(!usb.isCp21xxRestrictedPort)
throw e; throw e;
@ -718,18 +724,17 @@ public class DeviceTest {
usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_ODD); usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_ODD);
usb.write(_8n1); usb.write(_8n1);
data = telnet.read(4); data = telnet.read(4);
assertThat("19200/7O1", data, equalTo(_7o1));
usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_EVEN);
usb.write(_8n1);
data = telnet.read(4);
assertThat("19200/7E1", data, equalTo(_7e1));
if (usb.serialDriver instanceof CdcAcmSerialDriver) { if (usb.serialDriver instanceof CdcAcmSerialDriver) {
// not supported by arduino_leonardo_bridge.ino, other devices might support it // not supported by MCP2221, other CDC devices might support it
usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_MARK); assertThat("19200/8N1", data, equalTo(_8n1));
usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_SPACE);
} else { } else {
assertThat("19200/7O1", data, equalTo(_7o1));
usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_EVEN);
usb.write(_8n1);
data = telnet.read(4);
assertThat("19200/7E1", data, equalTo(_7e1));
usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_MARK); usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_MARK);
usb.write(_8n1); usb.write(_8n1);
data = telnet.read(4); data = telnet.read(4);
@ -758,19 +763,19 @@ public class DeviceTest {
data = usb.read(4); data = usb.read(4);
assertThat("19200/7E1", data, equalTo(_7e1)); assertThat("19200/7E1", data, equalTo(_7e1));
telnet.setParameters(19200, 7, 1, UsbSerialPort.PARITY_MARK);
telnet.write(_8n1);
data = usb.read(4);
assertThat("19200/7M1", data, equalTo(_7m1));
telnet.setParameters(19200, 7, 1, UsbSerialPort.PARITY_SPACE);
telnet.write(_8n1);
data = usb.read(4);
assertThat("19200/7S1", data, equalTo(_7s1));
if (usb.serialDriver instanceof CdcAcmSerialDriver) { if (usb.serialDriver instanceof CdcAcmSerialDriver) {
// not supported by arduino_leonardo_bridge.ino, other devices might support it ; // not supported by MCP2221, other CDC devices might support it
} else { } else {
telnet.setParameters(19200, 7, 1, UsbSerialPort.PARITY_MARK);
telnet.write(_8n1);
data = usb.read(4);
assertThat("19200/7M1", data, equalTo(_7m1));
telnet.setParameters(19200, 7, 1, UsbSerialPort.PARITY_SPACE);
telnet.write(_8n1);
data = usb.read(4);
assertThat("19200/7S1", data, equalTo(_7s1));
usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_ODD); usb.setParameters(19200, 7, 1, UsbSerialPort.PARITY_ODD);
telnet.setParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE); telnet.setParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
telnet.write(_8n1); telnet.write(_8n1);
@ -792,45 +797,44 @@ public class DeviceTest {
} }
} }
if (usb.serialDriver instanceof CdcAcmSerialDriver) { // shift stopbits into next byte, by using different databits
usb.setParameters(19200, 8, UsbSerialPort.STOPBITS_1_5, UsbSerialPort.PARITY_NONE); // a - start bit (0)
// software based bridge in arduino_leonardo_bridge.ino is to slow for real test, other devices might support it // o - stop bit (1)
} else { // d - data bit
// shift stopbits into next byte, by using different databits
// a - start bit (0)
// o - stop bit (1)
// d - data bit
// out 8N2: addddddd doaddddddddo // out 8N2: addddddd doaddddddddo
// 1000001 0 10001111 // 1000001 0 10001111
// in 6N1: addddddo addddddo // in 6N1: addddddo addddddo
// 100000 101000 // 100000 101000
usb.setParameters(19200, 8, UsbSerialPort.STOPBITS_1, UsbSerialPort.PARITY_NONE); usb.setParameters(19200, 8, UsbSerialPort.STOPBITS_1, UsbSerialPort.PARITY_NONE);
telnet.setParameters(19200, 6, 1, UsbSerialPort.PARITY_NONE); telnet.setParameters(19200, 6, 1, UsbSerialPort.PARITY_NONE);
usb.write(new byte[]{(byte)0x41, (byte)0xf1}); usb.write(new byte[]{(byte)0x41, (byte)0xf1});
data = telnet.read(2); data = telnet.read(2);
if (usb.serialDriver instanceof CdcAcmSerialDriver) {
// MCP2221 slightly slower, looks like 2 stop bits. could be different for other CDC devices
assertThat("19200/8N1", data, equalTo(new byte[]{1, 11}));
} else
assertThat("19200/8N1", data, equalTo(new byte[]{1, 5})); assertThat("19200/8N1", data, equalTo(new byte[]{1, 5}));
// out 8N2: addddddd dooaddddddddoo // out 8N2: addddddd dooaddddddddoo
// 1000001 0 10011111 // 1000001 0 10011111
// in 6N1: addddddo addddddo // in 6N1: addddddo addddddo
// 100000 110100 // 100000 110100
try { try {
usb.setParameters(19200, 8, UsbSerialPort.STOPBITS_2, UsbSerialPort.PARITY_NONE); usb.setParameters(19200, 8, UsbSerialPort.STOPBITS_2, UsbSerialPort.PARITY_NONE);
telnet.setParameters(19200, 6, 1, UsbSerialPort.PARITY_NONE); telnet.setParameters(19200, 6, 1, UsbSerialPort.PARITY_NONE);
usb.write(new byte[]{(byte) 0x41, (byte) 0xf9}); usb.write(new byte[]{(byte) 0x41, (byte) 0xf9});
data = telnet.read(2); data = telnet.read(2);
assertThat("19200/8N1", data, equalTo(new byte[]{1, 11})); assertThat("19200/8N1", data, equalTo(new byte[]{1, 11}));
} catch(UnsupportedOperationException e) { } catch(UnsupportedOperationException e) {
if(!usb.isCp21xxRestrictedPort) if(!usb.isCp21xxRestrictedPort)
throw e; throw e;
} }
try { try {
usb.setParameters(19200, 8, UsbSerialPort.STOPBITS_1_5, UsbSerialPort.PARITY_NONE); usb.setParameters(19200, 8, UsbSerialPort.STOPBITS_1_5, UsbSerialPort.PARITY_NONE);
// todo: could create similar test for 1.5 stopbits, by reading at double speed // todo: could create similar test for 1.5 stopbits, by reading at double speed
// but only some devices support 1.5 stopbits and it is basically not used any more // but only some devices support 1.5 stopbits and it is basically not used any more
} catch(UnsupportedOperationException ignored) { } catch(UnsupportedOperationException ignored) {
}
} }
} }
@ -883,8 +887,6 @@ public class DeviceTest {
usb.setParameters(baudRate, 8, 1, UsbSerialPort.PARITY_NONE); usb.setParameters(baudRate, 8, 1, UsbSerialPort.PARITY_NONE);
telnet.setParameters(baudRate, 8, 1, UsbSerialPort.PARITY_NONE); telnet.setParameters(baudRate, 8, 1, UsbSerialPort.PARITY_NONE);
int purgeTimeout = 250; int purgeTimeout = 250;
if(usb.serialDriver instanceof CdcAcmSerialDriver)
purgeTimeout = 500;
purgeWriteBuffer(purgeTimeout); purgeWriteBuffer(purgeTimeout);
// determine write buffer size // determine write buffer size
@ -1055,18 +1057,17 @@ public class DeviceTest {
@Test @Test
public void readBufferSize() throws Exception { public void readBufferSize() throws Exception {
// looks like devices perform USB read with full mReadEndpoint.getMaxPacketSize() size (32, 64, 512) // looks like devices perform USB read with full mReadEndpoint.getMaxPacketSize() size (16, 32, 64, 512)
// if the buffer is smaller than the received result, it is silently lost // if the buffer is smaller than the received result, it is silently lost
// //
// for buffer > packet size, but not multiple of packet size, the same issue happens, but typically // for buffer > packet size, but not multiple of packet size, the same issue happens, but typically
// only the last (partly filled) packet is lost. // only the last (partly filled) packet is lost.
if(usb.serialDriver instanceof CdcAcmSerialDriver)
return; // arduino sends each byte individually, so not testable here
byte[] data; byte[] data;
boolean purge = true; boolean purge = true;
usb.open(EnumSet.of(UsbWrapper.OpenCloseFlags.NO_IOMANAGER_START)); usb.open(EnumSet.of(UsbWrapper.OpenCloseFlags.NO_IOMANAGER_START));
usb.ioManager.setReadBufferSize(8); int len = Math.min(16, usb.serialPort.getReadEndpoint().getMaxPacketSize()/2); // 8 for MCP2221, else 16
usb.ioManager.setReadBufferSize(len/2);
usb.ioManager.start(); usb.ioManager.start();
usb.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE); usb.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE);
telnet.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE); telnet.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE);
@ -1075,13 +1076,15 @@ public class DeviceTest {
telnet.write("1aaa".getBytes()); telnet.write("1aaa".getBytes());
data = usb.read(4); data = usb.read(4);
assertThat(data, equalTo("1aaa".getBytes())); assertThat(data, equalTo("1aaa".getBytes()));
telnet.write(new byte[16]);
telnet.write(new byte[len]);
try { try {
data = usb.read(16); data = usb.read(len);
if (usb.serialDriver instanceof Cp21xxSerialDriver && usb.serialDriver.getPorts().size() == 1) if (usb.serialDriver instanceof Cp21xxSerialDriver && usb.serialDriver.getPorts().size() == 1)
assertNotEquals(0, data.length); // can be shorter or full length assertNotEquals(0, data.length); // can be shorter or full length
else if (usb.serialDriver instanceof ProlificSerialDriver) else if (usb.serialDriver instanceof CdcAcmSerialDriver ||
assertTrue("expected > 0 and < 16 byte, got " + data.length, data.length > 0 && data.length < 16); usb.serialDriver instanceof ProlificSerialDriver)
assertTrue("expected > 0 and < "+len+" byte, got " + data.length, data.length > 0 && data.length < len);
else // ftdi, ch340, cp2105 else // ftdi, ch340, cp2105
assertEquals(0, data.length); assertEquals(0, data.length);
} catch (IOException ignored) { } catch (IOException ignored) {
@ -1121,12 +1124,13 @@ public class DeviceTest {
telnet.write("2aaa".getBytes()); telnet.write("2aaa".getBytes());
data = usb.read(4, 8); data = usb.read(4, 8);
assertThat(data, equalTo("2aaa".getBytes())); assertThat(data, equalTo("2aaa".getBytes()));
telnet.write(new byte[16]); telnet.write(new byte[len]);
data = usb.read(16, 8); data = usb.read(len, len/2);
if (usb.serialDriver instanceof Cp21xxSerialDriver && usb.serialDriver.getPorts().size() == 1) if (usb.serialDriver instanceof Cp21xxSerialDriver && usb.serialDriver.getPorts().size() == 1)
assertNotEquals(0, data.length); // can be shorter or full length assertNotEquals(0, data.length); // can be shorter or full length
else if (usb.serialDriver instanceof ProlificSerialDriver) else if (usb.serialDriver instanceof CdcAcmSerialDriver ||
assertTrue("sporadic issue! expected > 0 and < 16 byte, got " + data.length, data.length > 0 && data.length < 16); usb.serialDriver instanceof ProlificSerialDriver)
assertTrue("sporadic issue! expected > 0 and < "+len+" byte, got " + data.length, data.length > 0 && data.length < len);
else // ftdi, ch340, cp2105 else // ftdi, ch340, cp2105
assertEquals(0, data.length); assertEquals(0, data.length);
telnet.write("2ccc".getBytes()); telnet.write("2ccc".getBytes());
@ -1146,8 +1150,6 @@ public class DeviceTest {
@Test @Test
// provoke data loss, when data is not read fast enough // provoke data loss, when data is not read fast enough
public void readBufferOverflow() throws Exception { public void readBufferOverflow() throws Exception {
if(usb.serialDriver instanceof CdcAcmSerialDriver)
telnet.writeDelay = 10; // arduino_leonardo_bridge.ino sends each byte in own USB packet, which is horribly slow
usb.open(); usb.open();
usb.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE); usb.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE);
telnet.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE); telnet.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE);
@ -1220,8 +1222,6 @@ public class DeviceTest {
if(usb.serialDriver instanceof Ch34xSerialDriver) if(usb.serialDriver instanceof Ch34xSerialDriver)
baudrate = 38400; baudrate = 38400;
int writeAhead = 5*baudrate/10; // write ahead for another 5 second read int writeAhead = 5*baudrate/10; // write ahead for another 5 second read
if(usb.serialDriver instanceof CdcAcmSerialDriver)
writeAhead = 50;
usb.open(EnumSet.of(UsbWrapper.OpenCloseFlags.NO_IOMANAGER_START)); usb.open(EnumSet.of(UsbWrapper.OpenCloseFlags.NO_IOMANAGER_START));
usb.ioManager.setReadTimeout(readTimeout); usb.ioManager.setReadTimeout(readTimeout);
@ -1270,16 +1270,10 @@ public class DeviceTest {
@Test @Test
public void writeSpeed() throws Exception { public void writeSpeed() throws Exception {
// see logcat for performance results // see logcat for performance results, speed is near physical limit at 11.5k
//
// CDC arduino_leonardo_bridge.ino has transfer speed ~ 100 byte/sec
// all other devices can get near physical limit:
// longlines=true:, speed is near physical limit at 11.5k
// longlines=false: speed is 3-4k for all devices, as more USB packets are required
usb.open(); usb.open();
usb.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE); usb.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE);
telnet.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE); telnet.setParameters(115200, 8, 1, UsbSerialPort.PARITY_NONE);
boolean longlines = !(usb.serialDriver instanceof CdcAcmSerialDriver);
int linenr = 0; int linenr = 0;
String line=""; String line="";
@ -1292,10 +1286,7 @@ public class DeviceTest {
for(int seconds=1; seconds<=5; seconds++) { for(int seconds=1; seconds<=5; seconds++) {
next += 1000; next += 1000;
while (System.currentTimeMillis() < next) { while (System.currentTimeMillis() < next) {
if(longlines) line = String.format("%060d,", linenr++);
line = String.format("%060d,", linenr++);
else
line = String.format("%07d,", linenr++);
usb.write(line.getBytes()); usb.write(line.getBytes());
expected.append(line); expected.append(line);
data.append(new String(telnet.read(0))); data.append(new String(telnet.read(0)));
@ -1576,34 +1567,32 @@ public class DeviceTest {
} }
Log.i(TAG, "average time per read " + (System.currentTimeMillis()-time)/i + " msec"); Log.i(TAG, "average time per read " + (System.currentTimeMillis()-time)/i + " msec");
if(!(usb.serialDriver instanceof CdcAcmSerialDriver)) { int diffLen;
int diffLen; usb.close();
usb.close(); // no issue with high transfer rate and long read timeout
// no issue with high transfer rate and long read timeout diffLen = readSpeedInt(5, -1, longTimeout);
diffLen = readSpeedInt(5, -1, longTimeout); if(usb.serialDriver instanceof Ch34xSerialDriver && diffLen == -1)
if(usb.serialDriver instanceof Ch34xSerialDriver && diffLen == -1) diffLen = 0; // todo: investigate last packet loss
diffLen = 0; // todo: investigate last packet loss assertEquals(0, diffLen);
assertEquals(0, diffLen); usb.close();
usb.close(); // date loss with high transfer rate and short read timeout !!!
// date loss with high transfer rate and short read timeout !!! diffLen = readSpeedInt(5, -1, shortTimeout);
diffLen = readSpeedInt(5, -1, shortTimeout);
assertNotEquals("sporadic issue!", 0, diffLen); assertNotEquals("sporadic issue!", 0, diffLen);
// data loss observed with read timeout up to 200 msec, e.g. // data loss observed with read timeout up to 200 msec, e.g.
// difference at 181 len 64 // difference at 181 len 64
// got 000020,0000021,0000030,0000031,0000032,0 // got 000020,0000021,0000030,0000031,0000032,0
// expected 000020,0000021,0000022,0000023,0000024,0 // expected 000020,0000021,0000022,0000023,0000024,0
// difference at 341 len 128 // difference at 341 len 128
// got 000048,0000049,0000066,0000067,0000068,0 // got 000048,0000049,0000066,0000067,0000068,0
// expected 000048,0000049,0000050,0000051,0000052,0 // expected 000048,0000049,0000050,0000051,0000052,0
// difference at 724 len 704 // difference at 724 len 704
// got 0000112,0000113,0000202,0000203,0000204, // got 0000112,0000113,0000202,0000203,0000204,
// expected 0000112,0000113,0000114,0000115,0000116, // expected 0000112,0000113,0000114,0000115,0000116,
// difference at 974 len 8 // difference at 974 len 8
// got 00231,0000232,0000234,0000235,0000236,00 // got 00231,0000232,0000234,0000235,0000236,00
// expected 00231,0000232,0000233,0000234,0000235,00 // expected 00231,0000232,0000233,0000234,0000235,00
}
} }
@Test @Test
@ -1808,12 +1797,7 @@ public class DeviceTest {
assertThat(usb.getControlLine(usb.serialPort::getCD), equalTo(inputLineFalse)); assertThat(usb.getControlLine(usb.serialPort::getCD), equalTo(inputLineFalse));
assertThat(usb.getControlLine(usb.serialPort::getRI), equalTo(usb.inputLinesOnlyRtsCts ? Boolean.FALSE : inputLineTrue)); assertThat(usb.getControlLine(usb.serialPort::getRI), equalTo(usb.inputLinesOnlyRtsCts ? Boolean.FALSE : inputLineTrue));
telnet.write(data); telnet.write(data);
if(usb.serialDriver instanceof CdcAcmSerialDriver) assertThat(Arrays.toString(data), usb.read(4), equalTo(data));
// arduino: control line feedback as serial_state notification is not implemented.
// It does not send w/o RTS or DTR, so these control lines can be partly checked here.
assertEquals(0, usb.read().length);
else
assertThat(Arrays.toString(data), usb.read(4), equalTo(data));
usb.write(data); usb.write(data);
assertThat(Arrays.toString(data), telnet.read(4), equalTo(data)); assertThat(Arrays.toString(data), telnet.read(4), equalTo(data));
@ -2312,20 +2296,25 @@ public class DeviceTest {
@Test @Test
public void setBreak() throws Exception { public void setBreak() throws Exception {
usb.open(); usb.open();
if (usb.serialDriver instanceof CdcAcmSerialDriver) {
// not supported by MCP2221, other CDC devices might support it
try {
usb.serialPort.setBreak(true);
fail("setBreak error expected");
} catch (IOException ignored) {
}
return;
}
telnet.setParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE); telnet.setParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
usb.setParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE); usb.setParameters(19200, 8, 1, UsbSerialPort.PARITY_NONE);
doReadWrite(""); doReadWrite("");
usb.serialPort.setBreak(true);
Thread.sleep(100); Thread.sleep(100);
usb.serialPort.setBreak(false); usb.serialPort.setBreak(false);
// RFC2217 has SET_CONTROL + REQ_BREAK_STATE request, but this is not supported by pyserial // RFC2217 has SET_CONTROL + REQ_BREAK_STATE request, but this is not supported by pyserial
// as there is no easy notification on <break> condition. By default break is returned as // as there is no easy notification on <break> condition. By default break is returned as
// 0 byte on Linux, see https://man7.org/linux/man-pages/man3/termios.3.html -> BRKINT // 0 byte on Linux, see https://man7.org/linux/man-pages/man3/termios.3.html -> BRKINT
byte[] data = telnet.read(1); byte[] data = telnet.read(1);
if (usb.serialDriver instanceof CdcAcmSerialDriver) { if(usb.isCp21xxRestrictedPort) {
// BREAK forwarding not implemented by arduino_leonardo_bridge.ino
assertThat("<break>", data, equalTo(new byte[]{}));
} else if(usb.isCp21xxRestrictedPort) {
assertThat("<break>", data, equalTo(new byte[]{0x55})); // send the last byte again? assertThat("<break>", data, equalTo(new byte[]{0x55})); // send the last byte again?
} else { } else {
assertThat("<break>", data, equalTo(new byte[]{0})); assertThat("<break>", data, equalTo(new byte[]{0}));

2
usbSerialForAndroid/src/androidTest/java/com/hoho/android/usbserial/util/UsbWrapper.java
View File

@ -152,7 +152,7 @@ public class UsbWrapper implements SerialInputOutputManager.Listener {
if(serialDriver.getDevice().getProductId() == UsbId.FTDI_FT231X) if(serialDriver.getDevice().getProductId() == UsbId.FTDI_FT231X)
writeBufferSize = 512; writeBufferSize = 512;
} else if (serialDriver instanceof CdcAcmSerialDriver) { } else if (serialDriver instanceof CdcAcmSerialDriver) {
writePacketSize = 64; writeBufferSize = 128; writePacketSize = 16; writeBufferSize = 32; // MCP2221 values, other devices might be different
} }
readBufferSize = writeBufferSize; readBufferSize = writeBufferSize;