Kramer Electronics VP-790 - Manual (Page 7)

VP-790 Protocol – Communication 3
Example: The Scaler Board answers to the BYTE
byOSDBrighntessSet(UWORD32 u32_value) API call. The return value is 0x00, i.e.
no error; the function has no other return values:
The data sent is (hex):
73 61 50 01 FF FF FF FF 00 00 00 00 00 00 00 00
53 41 50 01 FF FF FF FF
00 00 00 1D 00 00 00 00
74 50 01 00 00 00 00 00 00 00 00 0D 00 00 00 00
70 46 00 68 00 00 00 00 00 00 00 01 00
Again the RS232 receiver, this time the PC, acknowledges the message with (hex):
73 61 50 01 FF FF FF FF 00 00 00 00 00 00 00 00
1.4
5B
Data Types
The following input/output data types exist:
• BYTE
• Unsigned 8-bit value one single byte
• UWORD16: unsigned 16-bit value, MSB first (2 bytes)
• SWORD16: signed 16-bit value, two’s complement, MSB first (2 bytes)
• UWORD32 (a.k.a. DWORD): unsigned 32-bit value, MSB first (4 bytes)
• SWORD32: signed 32-bit value, two’s complement, MSB first (4 bytes)
• CHAR[]: array of UTF-8 characters preceded by its length sent as
UWORD32
Length of array 1 st char 2 nd char 3 rd char 4 th char
MSB … … LSB BYTE BYTE BYTE BYTE
• WHCAR[]: array of UTF-16 characters preceded by its length sent as
UWORD32
Length of array First WCHAR Second WHCAR
MSB … … LSB MSB LSB MSB LSB