PB375 U盘读写汇编程序 性价比超高的U盘读写模块-PB375,兼容CH375读写操作
1. 功能 ● 用于嵌入式系统/单片机读写U 盘、闪盘、闪存盘、USB 移动硬盘、USB 读卡器等。 ● 支持符合USB 相关规范基于Bulk-Only 传输协议的各种U 盘/闪存盘/外置硬盘。 ● 支持文件系统FAT12 和FAT16 及FAT32 ● 文件操作功能:新建、删除、读写数据,打开关闭文件等。 ● SPI接口,支持3.3V电平 ● 兼容CH375模块的操作命令 ● 单芯片解决方案,该模块只需要一个主控芯片外加少量的电容电阻便可,相对于51MCU+SL811/CH375的模块,无论模块尺寸还是成本都有着极大的优势。 ● 可以是模块提供,也可以是芯片提供(只需要简单的几个外围元件就可以了) 具体参数可以下载数据手册或者联系销售人员
基本不需要占用单片机系统的存储空间,最少只需要几个字节的RAM 和几百字节的代码。
下面就是一个很通用的台湾的单片机(可以是holtek 松翰 义隆 富晶等)用汇编操作PB375实现读写操作U盘的代码:
USB_FAIL EQU 0AAH USB_SUCC EQU 055H TRY_TIMES EQU 0FFH CMD_DiskReady EQU 071H CMD_FileCreate EQU 065H CMD_ByteWrite equ 07Ch CMD_FileClose equ 067h
//设置SPI 端口的输入输出 spi_ini: nop call i2c_delay b0bset spi_sdo_mod b0bset spi_sck_mod b0bset spi_cs_mod b0bclr spi_sdi_mod b0bset spi_cs ;not chose b0bset spi_sck b0bclr spi_sdo b0bclr spi_sdi
ret
/************************ SPI发一个字节,同时读一个字节 *************************/ spi_send:
nop clr epr_num clr spi_in b0bclr spi_sck spi_write_bit: b0bts0 epr_data_b jmp spi_write_h b0bclr spi_sdo jmp spi_read_com spi_write_h: b0bset spi_sdo spi_read_com: call i2c_delay b0bclr fc rlcm spi_in b0bts0 spi_sdi incms spi_in
b0bclr fc b0bset spi_sck call i2c_delay b0bclr spi_sck ;sck=0,data variable call i2c_delay
rlcm epr_data ;prepare for next incms epr_num nop b0bts1 epr_num_b jmp spi_write_bit call i2c_delay
ret
//发送命令 spi_send_command: b0bclr spi_cs b0mov rbank,#1 ; 写入命令码 mov a,cmd b0mov rbank,#0 b0mov epr_data,a call spi_send
b0mov rbank,#1 ;写入后续参数的长度 mov a,len b0mov rbank,#0 b0mov epr_data,a call spi_send
b0mov rbank,#1 ;写入后续参数 mov a,len b0mov rbank,#0 b0bts0 FZ jmp send_len_over ;len=0 b0mov temp,a b0mov Y,#1 b0mov Z,#sendbuf
send_len_byte: b0mov a,@YZ b0mov rbank,#0 b0mov epr_data,a call spi_send
b0mov rbank,#0 incms Z nop decms temp jmp send_len_byte
send_len_over: b0bset spi_cs call i2c_delay
;check the status mov a,#TRY_TIMES b0mov rbank,#1 mov trytime,a
check_status: b0mov rbank,#0 b0bclr spi_cs mov a,#0ffh b0mov epr_data,a call spi_send
b0bset spi_cs call i2c_delay
b0mov a,spi_in sub a,#0ffh b0bts0 FZ jmp wait_1ms ;模块操作尚未完成
b0mov a,spi_in sub a,#00h b0bts0 FZ jmp succ_quit_00 ;操作成功
fail_quit: b0bset spi_cs mov a,#USB_FAIL b0mov rbank,#1 mov usb_reslt,a b0mov rbank,#0 ret
wait_1ms: //延时 b0mov z,#0f7h b0mov y,#0e3h ;稳定oscillator,40ms delay_ms_02: b0bset fwdrst nop nop incms z jmp delay_ms_02 nop incms y jmp delay_ms_02
b0mov rbank,#1 decms trytime jmp check_status
jmp fail_quit
succ_quit_00: b0mov rbank,#0 b0bclr spi_cs mov a,#00h b0mov epr_data,a call spi_send
b0mov a,spi_in b0bts0 FZ jmp succ_quit
b0mov temp,a b0mov Y,#1 b0mov Z,#recvbuf
read_len_byte: mov a,#0 b0mov rbank,#0 b0mov epr_data,a call spi_send
b0mov a,spi_in b0mov @YZ,a b0mov rbank,#0 incms Z nop decms temp jmp read_len_byte succ_quit: b0bset spi_cs mov a,#USB_succ b0mov rbank,#1 mov usb_reslt,a b0mov rbank,#0 ret
testusb://测试主程序 call spi_ini //初始化spi b0mov rbank,#1 //发送U盘是否连接好命令 mov a,#CMD_DiskReady mov cmd,a mov a,#0 mov len,a b0mov rbank,#0 call spi_send_command b0mov rbank,#1 mov a,usb_reslt b0mov rbank,#0 sub a,#USB_succ b0bts1 FZ ret ;ok diskread ;sendbuf is 92+”TEST.DAT” //创建文件”TEST.DAT” b0mov rbank,#0 b0mov Y,#1 b0mov Z,#sendbuf mov a,#92 b0mov @yz,a incms Z mov a,#116 b0mov @yz,a incms Z mov a,#101 b0mov @yz,a incms Z mov a,#115 b0mov @yz,a incms Z mov a,#116 b0mov @yz,a incms Z mov a,#46 b0mov @yz,a incms Z mov a,#100 b0mov @yz,a incms Z mov a,#97 b0mov @yz,a incms Z mov a,#116 b0mov @yz,a incms Z
b0mov rbank,#1 mov a,#CMD_FileCreate //创建文件命令 mov cmd,a mov a,#10 mov len,a b0mov rbank,#0 call spi_send_command b0mov rbank,#1 mov a,usb_reslt b0mov rbank,#0 sub a,#USB_succ b0bts1 FZ ret
b0mov rbank,#0 b0mov Y,#1 b0mov Z,#sendbuf mov a,#19 b0mov @yz,a incms Z mov a,#33 b0mov @yz,a incms Z mov a,#34 b0mov @yz,a incms Z mov a,#35 b0mov @yz,a incms Z mov a,#36 b0mov @yz,a incms Z mov a,#37 b0mov @yz,a incms Z mov a,#38 b0mov @yz,a incms Z mov a,#39 b0mov @yz,a incms Z mov a,#40 b0mov @yz,a incms Z mov a,#41 b0mov @yz,a
b0mov rbank,#1 mov a,#CMD_ByteWrite //写入数据 mov cmd,a mov a,#10 mov len,a b0mov rbank,#0 call spi_send_command
b0mov rbank,#1 mov a,#CMD_FileClose //关闭文件 mov cmd,a mov a,#1 mov len,a b0mov rbank,#0 call spi_send_command
ret
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