| 1159 | } |
| 1160 | |
| 1161 | SIGNAL(TWI_vect) { |
| 1162 | switch (TW_STATUS) { |
| 1163 | // All Master |
| 1164 | case TW_START: // sent start condition |
| 1165 | case TW_REP_START: // sent repeated start condition |
| 1166 | // copy device address and r/w bit to output register and ack |
| 1167 | TWDR = twi_slarw; |
| 1168 | twi_reply(1); |
| 1169 | break; |
| 1170 | |
| 1171 | // Master Transmitter |
| 1172 | case TW_MT_SLA_ACK: // slave receiver acked address |
| 1173 | case TW_MT_DATA_ACK: // slave receiver acked data |
| 1174 | // if there is data to send, send it, otherwise stop |
| 1175 | if (twi_masterBufferIndex < twi_masterBufferLength) { |
| 1176 | // copy data to output register and ack |
| 1177 | TWDR = twi_masterBuffer[twi_masterBufferIndex++]; |
| 1178 | twi_reply(1); |
| 1179 | } else { |
| 1180 | twi_stop(); |
| 1181 | } |
| 1182 | break; |
| 1183 | |
| 1184 | case TW_MT_SLA_NACK: // address sent, nack received |
| 1185 | twi_error = TW_MT_SLA_NACK; |
| 1186 | twi_stop(); |
| 1187 | break; |
| 1188 | |
| 1189 | case TW_MT_DATA_NACK: // data sent, nack received |
| 1190 | twi_error = TW_MT_DATA_NACK; |
| 1191 | twi_stop(); |
| 1192 | break; |
| 1193 | |
| 1194 | case TW_MT_ARB_LOST: // lost bus arbitration |
| 1195 | twi_error = TW_MT_ARB_LOST; |
| 1196 | twi_releaseBus(); |
| 1197 | break; |
| 1198 | |
| 1199 | // Master Receiver |
| 1200 | case TW_MR_DATA_ACK: // data received, ack sent |
| 1201 | // put byte into buffer |
| 1202 | twi_masterBuffer[twi_masterBufferIndex++] = TWDR; |
| 1203 | |
| 1204 | case TW_MR_SLA_ACK: // address sent, ack received |
| 1205 | // ack if more bytes are expected, otherwise nack |
| 1206 | if (twi_masterBufferIndex < twi_masterBufferLength) { |
| 1207 | twi_reply(1); |
| 1208 | } else { |
| 1209 | twi_reply(0); |
| 1210 | } |
| 1211 | break; |
| 1212 | |
| 1213 | case TW_MR_DATA_NACK: // data received, nack sent |
| 1214 | // put final byte into buffer |
| 1215 | twi_masterBuffer[twi_masterBufferIndex++] = TWDR; |
| 1216 | |
| 1217 | case TW_MR_SLA_NACK: // address sent, nack received |
| 1218 | twi_stop(); |
nothing calls this directly
no test coverage detected