Shift Registers - Tutorial 5, Bank Interleaving

1//
2//   Tutorial 5 - use of ez_SPI8 library,
3//   Demonstration  of SIPO bank interleaving - 8 x physical SIPOs
4//   each mapped to an individual  bank but with the same 3-wire digital
5//   pin microcontroller interface.
6//
7//   The sketch sets up each single SIPO bank with a different binary 8bit
8//   (8  pin) pattern which is then xferred to the physical single SIPO IC.
9//   The sketch  mimics the strobe sketch by using bank interleaving.
10//   To note is the small  amount of SIPO8 library code that is used.
11//
12//   Ron D Bentley, Stafford,  UK
13//   April 2021
14//
15//   This example and code is in the public domain  and
16//   may be used without restriction and without warranty.
17//
18
19#include  <ez_SIPO8_lib.h>
20
21int bank_id;
22
23#define Num_SIPOs   8
24#define Num_timers  0
25
26SIPO8 my_SIPOs(Num_SIPOs, Num_timers); // initiate the class for the  tutorial
27
28uint8_t bank_ids[Num_SIPOs]; // one bank_id per SIPO bank
29uint8_t  bank;
30
31void setup() {
32  Serial.begin(9600);
33  // create banks of 1 x  SIPO, all of same 3-wire interface and initialise
34  // with each strobe pattern  - 0b00000001, 0b00000010, 0b00000100, etc.
35  // create_bank params are: data  pin, clock pin, latch pin, number of SIPOs this bank
36  for (bank = 0; bank <  Num_SIPOs; bank++) {
37    bank_ids[bank] = my_SIPOs.create_bank(8, 10, 9, 1);
38    if (bank_ids[bank] == create_bank_failure) {
39      Serial.println(F("failed  to create bank"));
40      Serial.flush();
41      exit(0);
42    }
43    //  now set up the strobe patterns in the bank's single SIPO, relative SIPO address  is 0
44    // sliding pattern of 1's starting at 0b00000001
45    my_SIPOs.set_bank_SIPO(bank_ids[bank],  0, 1 << bank); // set up this bank's strobe pattern
46  }
47  // print the bank  data and pin statuses for confirmation/inspection
48  my_SIPOs.print_SIPO_data();
49  my_SIPOs.print_pin_statuses();
50}
51
52void loop() {
53  // scroll through  every SIPO bank (interleave) and xfer the bank's pins
54  // according to the direction  for shift out.
55  bool msb_or_lsb = MSBFIRST; // starting direction
56  do {
57    for (bank = 0; bank < Num_SIPOs; bank++) {
58      my_SIPOs.xfer_bank(bank,  msb_or_lsb); // xfer out this bank's SIPO pins
59      delay(50);
60    }
61    msb_or_lsb = !msb_or_lsb; // switch direction
62  } while (true);
63}
64