saleae-logic16: claim device before using it

[libsigrok.git] / hardware / uni-t-dmm / protocol.c

diff --git a/hardware/uni-t-dmm/protocol.c b/hardware/uni-t-dmm/protocol.c
index 6b2abebfa0e9ced85f59c35cbbc25d58ab86f656..0c6d9efe414605ab8c7ca06e3f37cb5fe97abcb4 100644 (file)
--- a/hardware/uni-t-dmm/protocol.c
+++ b/hardware/uni-t-dmm/protocol.c
@@ -49,25 +49,6 @@
  *  f0 00 00 00 00 00 00 00 (no data bytes)
  *  f2 55 77 00 00 00 00 00 (2 data bytes, 0x55 and 0x77)
  *  f1 d1 00 00 00 00 00 00 (1 data byte, 0xd1)
- *
- * Chips and serial settings used in UNI-T DMMs (and rebranded ones):
- *  - Tecpel DMM-8061: ? (very likely Fortune Semiconductor FS9721_LP3)
- *  - UNI-T UT108: ?
- *  - UNI-T UT109: ?
- *  - UNI-T UT30A: ?
- *  - UNI-T UT30E: ?
- *  - UNI-T UT60A: Fortune Semiconductor FS9721_LP3 (?)
- *  - UNI-T UT60E: Fortune Semiconductor FS9721_LP3 (?)
- *  - UNI-T UT60G: ?
- *  - UNI-T UT61B: ?
- *  - UNI-T UT61C: ?
- *  - UNI-T UT61D: Fortune Semiconductor FS9922-DMM4
- *  - UNI-T UT61E: Cyrustek ES51922
- *  - UNI-T UT70B: ?
- *  - Voltcraft VC-820: Fortune Semiconductor FS9721_LP3
- *  - Voltcraft VC-830: Fortune Semiconductor FS9922-DMM4
- *  - Voltcraft VC-840: Fortune Semiconductor FS9721_LP3
- *  - ...
  */
 
 static void decode_packet(struct sr_dev_inst *sdi, int dmm, const uint8_t *buf,
@@ -239,10 +220,24 @@ static int get_and_handle_data(struct sr_dev_inst *sdi, int dmm, void *info)
 
        devc->bufoffset = 0;
 
-       /* Append the 1-7 data bytes of this chunk to pbuf. */
+       /*
+        * Append the 1-7 data bytes of this chunk to pbuf.
+        *
+        * Special case:
+        * DMMs with Cyrustek ES51922 chip need serial settings of
+        * 19230/7o1. The WCH CH9325 UART to USB/HID chip used in (some
+        * versions of) the UNI-T UT-D04 cable however, will also send
+        * the parity bit to the host in the 8-byte data chunks. This bit
+        * is encoded in bit 7 of each of the 1-7 data bytes and must thus
+        * be removed in order for the actual ES51922 protocol parser to
+        * work properly.
+        */
        num_databytes_in_chunk = buf[0] & 0x0f;
-       for (i = 0; i < num_databytes_in_chunk; i++)
-               pbuf[devc->buflen++] = buf[1 + i];
+       for (i = 0; i < num_databytes_in_chunk; i++, devc->buflen++) {
+               pbuf[devc->buflen] = buf[1 + i];
+               if (udmms[dmm].packet_parse == sr_es51922_parse)
+                       pbuf[devc->buflen] &= ~(1 << 7);
+       }
 
        /* Now look for packets in that data. */
        while ((devc->buflen - devc->bufoffset) >= udmms[dmm].packet_size) {