github/esphome
2
0
Fork 0
mirror of https://github.com/esphome/esphome.git synced 2026-10-06 10:56:43 +00:00
Code Issues Packages Projects Releases Wiki Activity

[modbus] Add server support for read/write multiple registers (0x17) (#17357)

Browse Source 
Co-authored-by: J. Nick Koston <nick@koston.org>
This commit is contained in:
Josef Zweck
2026-08-07 14:17:11 -05:00
committed by GitHub
co-authored by J. Nick Koston
parent 2e1c517821
commit c24e61439b
7 changed files with 407 additions and 31 deletions
Download Patch File Download Diff File Expand all files Collapse all files
tests/components/modbus/modbus_helpers_test.cpp
+12
View File
@@ -92,6 +92,18 @@ TEST(ModbusClientFrameLength, ReadWriteMultipleByteCountCappedAtSpecLimit) {
EXPECT_EQ(client_pdu_length(pdu, sizeof(pdu)), 10 + MAX_NUM_OF_REGISTERS_TO_WRITE_RW * 2);
}
TEST(ModbusClientFrameLength, ReadWriteMultipleUsesByteCount) {
// read start(2) + read qty(2) + write start(2) + write qty(2) + byte count(1) then data
const uint8_t frame[] = {0x01, 0x17, 0x9C, 0xB9, 0x00, 0x02, 0x9C, 0x41, 0x00, 0x02, 0x04, 0xAA, 0xBB, 0xCC, 0xDD};
EXPECT_EQ(client_frame_length(frame, sizeof(frame)), 13 + 4);
}
TEST(ModbusClientFrameLength, ReadWriteMultipleMissingByteCount) {
// header present up to the write quantity but the byte count byte (frame[10]) is absent
const uint8_t frame[] = {0x01, 0x17, 0x9C, 0xB9, 0x00, 0x02, 0x9C, 0x41, 0x00, 0x02};
EXPECT_EQ(client_frame_length(frame, sizeof(frame)), 13);
}
TEST(ModbusClientFrameLength, WriteMultipleMissingByteCount) {
const uint8_t frame[] = {0x01, 0x10, 0x00, 0x00, 0x00, 0x02};
EXPECT_EQ(client_frame_length(frame, sizeof(frame)), 9);