I2CRam is a generic i2c Ram/Rom, with configurable size and Control Code (address). Right-Click on it and select "Properties" to set/edit properies:
- Control Code:fixed part of the slave i2 address (see explanation below).
- Size bytes:
Memory size in bytes
For memory size <= 256 i2c Ram expects 1 Ram address byte.
For memory size > 256 i2c Ram expects 2 Ram address bytes.
- Persistent:
Sets the memory persistency.
If true, it will keep data betwen sessions (save circuit).
If false, memory data will be deleted at circuit power-off.
About Control Code:
"Control code" is the fixed part of the slave i2 address, wich is part of the "control byte":
Control Byte:
X X X X A0 A1 A2 RW
Control Code:
X X X X 0 0 0
Slave_i2c_address = "control code" + A2 A1 A0
Control byte = ( Slave_i2c_address << 1 ) + RW? 1:0
Default control code in simulide i2c = 80 (decimal):
1 0 1 0 0 0 0
If A0-A2 pins are low, i2c address = control code.
In write operations control byte to send after start condition:
X X X X A0 A1 A2 0
With simulide defaults and Ax pins low:
1 0 1 0 0 0 0 0
For reading operations:
1 0 1 0 0 0 0 1
If you set A0 high in a second i2c, control byte to write:
1 0 1 0 0 0 1 0
Pins Ax set lower 3 bits, so you can choose betwen several i2c with same "control code" in same bus.
If they are unused they read as 0 in simulide.
