M_ID, C_ID usage
Each one of the four pins of the M_ID and C_ID can be connected to
either Vcc, Gnd, S_ID1 or S_ID0.
After 2 uclk cycles each of the pins is translated to 2 bits (Table 1)
and therefore the 8 bit words for the Model and the Constructor get
defined.
The signals S_ID0 and S_ID1 provide 2 opposite clocks (when one is ‘0’
the other is ‘1’ and vice-versa).
M_ID, C_ID pin connected to | Corresponding pair of bits |
---|---|
Gnd | 00 |
S_ID1 | 10 |
S_ID0 | 01 |
Vcc | 11 |
Table 1: Options for M_ID/ C_ID pins and corresponding bits translation
The following examples clearify the concept:
Model Word | M_ID [3] | M_ID [2] | M_ID [1] | M_ID [0] |
---|---|---|---|---|
00000000 | Gnd | Gnd | Gnd | Gnd |
00000001 | Gnd | Gnd | Gnd | S_ID0 |
00000101 | Gnd | Gnd | S_ID0 | S_ID0 |
00001010 | Gnd | Gnd | S_ID1 | S_ID1 |
11010110 | Vcc | S_ID0 | S_ID0 | S_ID1 |
Table 2: Examples of Model words with their M_ID[] pins configuration
PS: We have selected such an implementation of the Model and Constructor in order to save 4 I/O pins!
_Back to the Hints n' Tips Guide_
E.Gousiou, March 2012