| 79 | } |
| 80 | |
| 81 | void SerialFlashChip::read(uint32_t addr, void *buf, uint32_t len) |
| 82 | { |
| 83 | uint8_t *p = (uint8_t *)buf; |
| 84 | uint8_t b, f, status, cmd; |
| 85 | |
| 86 | memset(p, 0, len); |
| 87 | f = flags; |
| 88 | SPIPORT.beginTransaction(SPICONFIG); |
| 89 | b = busy; |
| 90 | if (b) { |
| 91 | // read status register ... chip may no longer be busy |
| 92 | CSASSERT(); |
| 93 | if (flags & FLAG_STATUS_CMD70) { |
| 94 | SPIPORT.transfer(0x70); |
| 95 | status = SPIPORT.transfer(0); |
| 96 | if ((status & 0x80)) b = 0; |
| 97 | } else { |
| 98 | SPIPORT.transfer(0x05); |
| 99 | status = SPIPORT.transfer(0); |
| 100 | if (!(status & 1)) b = 0; |
| 101 | } |
| 102 | CSRELEASE(); |
| 103 | if (b == 0) { |
| 104 | // chip is no longer busy :-) |
| 105 | busy = 0; |
| 106 | } else if (b < 3) { |
| 107 | // TODO: this may not work on Spansion chips |
| 108 | // which apparently have 2 different suspend |
| 109 | // commands, for program vs erase |
| 110 | CSASSERT(); |
| 111 | SPIPORT.transfer(0x06); // write enable (Micron req'd) |
| 112 | CSRELEASE(); |
| 113 | delayMicroseconds(1); |
| 114 | cmd = 0x75; //Suspend program/erase for almost all chips |
| 115 | // but Spansion just has to be different for program suspend! |
| 116 | if ((f & FLAG_DIFF_SUSPEND) && (b == 1)) cmd = 0x85; |
| 117 | CSASSERT(); |
| 118 | SPIPORT.transfer(cmd); // Suspend command |
| 119 | CSRELEASE(); |
| 120 | if (f & FLAG_STATUS_CMD70) { |
| 121 | // Micron chips don't actually suspend until flags read |
| 122 | CSASSERT(); |
| 123 | SPIPORT.transfer(0x70); |
| 124 | do { |
| 125 | status = SPIPORT.transfer(0); |
| 126 | } while (!(status & 0x80)); |
| 127 | CSRELEASE(); |
| 128 | } else { |
| 129 | CSASSERT(); |
| 130 | SPIPORT.transfer(0x05); |
| 131 | do { |
| 132 | status = SPIPORT.transfer(0); |
| 133 | } while ((status & 0x01)); |
| 134 | CSRELEASE(); |
| 135 | } |
| 136 | } else { |
| 137 | // chip is busy with an operation that can not suspend |
| 138 | SPIPORT.endTransaction(); // is this a good idea? |
no outgoing calls
no test coverage detected