MS522低功耗寻卡
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2022-05-14 09:21:33
方案:单片机处于低功耗模式,MS522处于软掉电模式。单片机用RTC定时(比如每隔1s)唤醒,单片机唤醒后唤醒MS522寻卡。寻到卡则做进一步处理,否则MS522继续进入软掉电模式,单片机进入低功耗模式。 手册相关内容 参考资料: MS522手册:https://wenku.baidu.com/vi ......
方案:单片机处于低功耗模式,ms522处于软掉电模式。单片机用rtc定时(比如每隔1s)唤醒,单片机唤醒后唤醒ms522寻卡。寻到卡则做进一步处理,否则ms522继续进入软掉电模式,单片机进入低功耗模式。
if (1 == flag_rtc_wakeup) { flag_rtc_wakeup = 0; pcd_soft_powerup(); if (pcd_fast_detect() == true) { //todo } pcd_soft_powerdown(); }
void pcd_soft_powerdown(void) { write_rawrc(commandreg, pcd_nocmdchange | (1 << 4)); } void pcd_soft_powerup(void) { uint8_t count = 0; write_rawrc(commandreg, pcd_nocmdchange & (~(1 << 4))); do { // wait for the powerdown bit in commandreg to be cleared (max 3x10us) delay_10us(1); } while ((read_rawrc(commandreg) & (1 << 4)) && (++count) < 3); }
手册相关内容
//快速寻卡函数 bool pcd_fast_detect(void) { uint8_t valid_bits = 7; uint8_t command = picc_reqidl; uint8_t wait_irq = 0x30; // rxirq and idleirq uint8_t n; uint16_t i; clear_bit_mask(collreg, 0x80); // valuesaftercoll=1 => bits received after collision are cleared. // write_rawrc(commandreg, pcd_idle); // stop any active command. write_rawrc(comirqreg, 0x7f); // clear all seven interrupt request bits set_bit_mask(fifolevelreg, 0x80); // flushbuffer = 1, fifo initialization write_rawrc(fifodatareg, command); // write senddata to the fifo write_rawrc(bitframingreg, valid_bits); // bit adjustments write_rawrc(commandreg, pcd_transceive); // execute the command set_bit_mask(bitframingreg, 0x80); // startsend=1, transmission of data starts i = 3; //根据时钟频率修改 while (1) { n = read_rawrc(comirqreg); // comirqreg[7..0] bits are: set1 txirq rxirq idleirq hialertirq loalertirq errirq timerirq if (n & wait_irq) { // one of the interrupts that signal success has been set. //debug("t\r\n"); break; } if (n & 0x01) { // timer interrupt - nothing received in time //debug("f\r\n"); return false; } if (--i == 0) { // the emergency break. if all other conditions fail we will eventually terminate on this one. communication with the mfrc522 might be down. //debug("i\r\n"); return false; } } return true; }
void pcd_reset(void) { rc522_rst_on; write_rawrc(commandreg, pcd_resetphase); uint8_t count = 0; do { // wait for the powerdown bit in commandreg to be cleared (max 3x40us) delay_10us(4); } while ((read_rawrc(commandreg) & (1 << 4)) && (++count) < 3); // tauto=1; timer starts automatically at the end of the transmission in all communication modes at all speeds.10us write_rawrc(tmodereg, 0x80); write_rawrc(tprescalerreg, 0x43); // 10μs // reload timer with 0x1e = 30, ie 0.3ms before timeout. write_rawrc(treloadregh, 0x00); write_rawrc(treloadregl, 0x1e); write_rawrc(txautoreg, 0x40); write_rawrc(modereg, 0x3d); //和mifare卡通讯,crc初始值0x6363 pcd_antenna_on(); }
参考资料:
ms522手册:https://wenku.baidu.com/view/6f5bcabcbcd126fff6050b77
关于软掉电模式的讨论:
软掉电模式demo:https://github.com/akellai/rfid-music/blob/master/rfid_promini/rfid_promini.ino
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