diff --git a/.github/workflows/hil.yml b/.github/workflows/hil.yml
index 4e0b929de..f8c964f6f 100644
--- a/.github/workflows/hil.yml
+++ b/.github/workflows/hil.yml
@@ -29,7 +29,7 @@ env:
 jobs:
   build-espflash:
     name: Build espflash
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     steps:
       - uses: actions/checkout@v4
         with:
@@ -99,7 +99,7 @@ jobs:
 
       - name: save-image/write-bin test
         run: |
-          bash espflash/tests/scripts/save-image_write-bin.sh ${{ matrix.board.mcu }} ${{ matrix.board.flag }} ${{ env.ESPFLASH_APP }}
+          bash espflash/tests/scripts/save-image_write-bin.sh ${{ matrix.board.mcu }} ${{ env.ESPFLASH_APP }}
           bash espflash/tests/scripts/monitor.sh
 
       # - name: erase-region test
diff --git a/espflash/tests/data/README.md b/espflash/tests/data/README.md
new file mode 100644
index 000000000..29e5cd519
--- /dev/null
+++ b/espflash/tests/data/README.md
@@ -0,0 +1,7 @@
+The elf files under this folder have been generated using `esp-generate@0.2.2`:
+
+```
+esp-generate --chip=$CHIP --headless $CHIP
+cd $CHIP
+cargo build --release
+```
diff --git a/espflash/tests/data/esp32 b/espflash/tests/data/esp32
index b0120b65f..817a07b17 100755
Binary files a/espflash/tests/data/esp32 and b/espflash/tests/data/esp32 differ
diff --git a/espflash/tests/data/esp32c2 b/espflash/tests/data/esp32c2
index 550cfff77..f57da5b34 100755
Binary files a/espflash/tests/data/esp32c2 and b/espflash/tests/data/esp32c2 differ
diff --git a/espflash/tests/data/esp32c3 b/espflash/tests/data/esp32c3
index 7317bd898..814be43cc 100755
Binary files a/espflash/tests/data/esp32c3 and b/espflash/tests/data/esp32c3 differ
diff --git a/espflash/tests/data/esp32c6 b/espflash/tests/data/esp32c6
index 4f5d44c71..f8f634744 100755
Binary files a/espflash/tests/data/esp32c6 and b/espflash/tests/data/esp32c6 differ
diff --git a/espflash/tests/data/esp32h2 b/espflash/tests/data/esp32h2
index 3107c716c..311c63056 100755
Binary files a/espflash/tests/data/esp32h2 and b/espflash/tests/data/esp32h2 differ
diff --git a/espflash/tests/data/esp32s2 b/espflash/tests/data/esp32s2
index c275fee3a..51f29f96c 100755
Binary files a/espflash/tests/data/esp32s2 and b/espflash/tests/data/esp32s2 differ
diff --git a/espflash/tests/data/esp32s3 b/espflash/tests/data/esp32s3
index 1dbf4c138..a5ee765cc 100755
Binary files a/espflash/tests/data/esp32s3 and b/espflash/tests/data/esp32s3 differ
diff --git a/espflash/tests/scripts/save-image_write-bin.sh b/espflash/tests/scripts/save-image_write-bin.sh
index c9a160b78..0529f9b10 100644
--- a/espflash/tests/scripts/save-image_write-bin.sh
+++ b/espflash/tests/scripts/save-image_write-bin.sh
@@ -1,6 +1,11 @@
 #!/usr/bin/env bash
 
-result=$(espflash save-image --merge --chip $1 $2 $3 app.bin 2>&1)
+# if $1 is esp32c2, create an variable that contains `-x 26mhz`
+if [[ $1 == "esp32c2" ]]; then
+    freq="-x 26mhz"
+fi
+
+result=$(espflash save-image --merge --chip $1 $freq $2 app.bin 2>&1)
 echo "$result"
 if [[ ! $result =~ "Image successfully saved!" ]]; then
     exit 1