KRAMER: SIMPLE CREATIVE TECHNOLOGY
Communication Protocol
7 Communication Protocol
RS-232 communication with the 7508 complies with the following protocol.
The protocol uses 4 bytes of information, and data is at 9600 baud, with no
parity, 8 data bits and 1 stop bit.
Table 4: Structure of the Protocol
7 6 5 4 3 2 1 0
2nd byte
Note that the MSB’s of the DATA (D7) and the EXTENDED DATA (E7) are in the fourth byte.
Terminology:
• TO PC is the “DESTINATION BIT”
• I4..I0 is the “INSTRUCTION”
• D7..D0 is the “DATA”
• E7..E0 is the “EXTENDED DATA”
• A0 is the “LSB of the MACHINE ADDRESS”
The destination bit, TO PC, is 0 when sending from the PC to the machine, or 1 when sending from the machine to the PC.
Table 5: Instruction Set for the 7508
# INSTRUCTION
I5 I4 I3 I2 I1 I0
Read back-panel DIP-switch 1 (video format CV/YC)
10 Write EEPROM data – low address 0 0 1 0 1 0
11 Read EEPROM data – low address 0 0 1 0 1 1
12 Write I²C 0 0 1 1 0 0
13 Read I²C 0 0 1 1 0 1
1 Note that the MSB’s of the DATA (D7) and the EXTENDED DATA (E7) are in the fourth byte
