[U-Boot-Users] Is hardware handshake necessary for SMC1?

SAM SONG samsongshu at yahoo.com.cn
Sun Dec 21 20:04:48 CET 2003


Hi,you all,
 
After successfully porting on LITE_DW,I tried my best to make my design board work.But no good serial output by now.At first,there were some characters displayed on the screen in a state disorder with help of BDI2000 and GDB.I,HOWEVER,cannot see them after making some changes on hardware and software.For no CPLD on my board,there is no hardware handshake circuit.Does it matter?
 
U-Boot 1.0.0 (Dec 17 2003 - 14:56:31)    
                                           ««HH?K.?.5Qaai.5).I5?..?5       ÿ
CPU:   PPC823EZTnnB2 at 64 MHz:.YHNH-($Ti*k  
U-Boot 1.0.0 (Dec 17 2003 - 14:56:31)    

 
My MPC8xx connects the RS232 transceiver chip as following:
 
1.SMC1
 
MPC823E                             MAX3225
PB24-SMC1TXD    --------------     T1IN
PB25-SMC1RXD   --------------      R1OUT
PB22-EN              -------------       FOFF
 
Related code in serial.c:
 
#if defined(CONFIG_RPXLITE) || defined(CONFIG_RPXCLASSIC)
 
cp->cp_pbpar &=~0x00000200;   /* Added by SAM */
cp->cp_pbdir |= 0x00000200;     
cp->cp_pbodr &=~0x00000200;  
cp->cp_pbdat |= 0x00000200;     /* Set PB22 1. ENABLE RS232*/
  
#endif /* CONFIG_RPXLITE */

2.SCC3
 
MPC823E                                MAX3225
PB24-SCC3TXD3   --------------        T1IN
PB25-SCC3RXD3   --------------        R1OUT
PC13-RTS3           --------------        T2IN
PB23-CTS             --------------        R2OUT
PB22-EN               -------------         FOFF                   
 
Related code in serial.c:
 
-------
 
#if (SCC_INDEX == 2) && defined(CONFIG_MPC823)    /* [SAM]  */

cp->cp_pbpar   |=  0x000000c0;   /* Defining PB25=TXD3 PB24=RXD3 */
cp->cp_pbdir    |=  0x000000c0;    
cp->cp_pbodr  &= ~0x000000c0; 
 
 -------
 
#if defined(CONFIG_RPXLITE) || defined(CONFIG_RPXCLASSIC
 
cp_pbpar &=~0x00000200;     
cp->cp_pbdat |= 0x00000200; 
cp->cp_pbdir |= 0x00000200;      
cp->cp_pbodr &=~0x00000200;     /* Set PB22 1. ENABLE RS232*/
 
im->im_ioport.iop_pcpar |= (ushort) 0x0004;   /* Let PC13 = RTS3 */
im->im_ioport.iop_pcdat &=~(ushort) 0x0004;
im->im_ioport.iop_pcdir &=~(ushort) 0x0004;   /* Enable RTS3*/
  
#endif /* CONFIG_RPXLITE */
 
Thanks for reading & any help.
 
Best regards,
 
SAM
 
***Sorry for sending the draft to mail list just now ***
 

 

 




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