Renesas Asynchronous SH7145F manual

APPLICATION NOTE REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 1 of 17 SH7145F Asynchronou s Serial Data Transmission/Re ception Summary The SH7144 se ries is a sin gle-chip m icroprocessor based on t he SH-2 RISC (Reduced In struction Set Com puter) CPU core and inte grating a num ber of peripheral funct ions. This application note describes asynchr[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 2 of 17 1. Specifications As shown in figure 1, asynchronous serial data transmission is performed using channel 1 (ch1) of the SCI module of the SH7145F. In th is task example 3 bytes of se rial data are received by the SH7145, and th e receive da[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 3 of 17 2 Functions Used In this task example the SCI (Serial Communication Interface) is used to perform asynchronous serial data transmission /reception. Figure 2 shows a block diagram of channel 1 (ch1) of the SCI modul e. T he func tio ns of t [...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 4 of 17 • On-C hip Pe rip her al Clo ck P φ This is the reference clock for ope ration of on-chip peripheral functions. T he clock signal is generated b y a clock oscil lator. • Receive Shift Register (RSR_1) This register is u sed to receive [...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 5 of 17 • Bit Rate Register ( BRR_1 ) This 8 -bit r egiste r is use d to a dj ust the bi t rate . T he SCI ha s indep end ent b aud r ate gene rat ors for the individu al channels, allo wing differen t bit rates to be set for each. See the hardwa[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 6 of 17 3. Operation Figure 3 s hows the operat ion of asy nchron ous mode data t ransmiss ion in the task exam ple. To help explain figure 3, table 3 lists the software and hard ware processing that is perfor med. 0 0 (1) (2) (3) (4) (5) (6) (7) ([...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 7 of 17 Table 3 Processing Software Processing Hardware Process ing (1) — RSR_1 receives seri al data and transfers it to RDR_1 (2) — Set RDRF flag in SSR_1 to 1 (3) Read data from RDR_1 (4) Clear RDRF flag in SSR_1 to 0 ( 5 ) W r i t er e c e [...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 8 of 17 4. Soft w are (1) Module Descriptions Table 4 lists the mod ules used in the task e xample. Table 4 Module Descriptions Module Label Function Main routine main Calls module s SCI routine init_sci Initial sett ings of SCI 1 Receive routi ne [...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 9 of 17 Table 6 On-Chip Register Descrip tions Register Bit Set Value Function MSTCR1 MSTP17 0 Module standby c ontrol register 1 SCI1 s tandby control bit Standby cancelled when MSTP17 = 0 SCR_1 H'70 Serial c ontrol regist er 1 (SCI_1) Transm[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 10 of 17 Register Bit Set Value Function SMR_1 MP 0 Multiprocess or mode (enabled in asynchronous mode onl y) Multiprocess or communication disabl ed when 0 CKS1 CKS2 0 0 Clock s elect 1, 0 When val ue is 00, P φ cl ock sel ected using on-c hip ba[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 11 of 17 5. Flowcharts (1) Main Routine main() init_sci() rcv_sci() rcv_sci() rcv_sci() Initialize SCI module Receive 1st byte of data Receive 2nd byte of data Receive 3rd byte of data[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 12 of 17 (2) SCI1 Initialize Routine No Ye s Cancel SCI1 module standby status Clear to 0 bits TIE, RIE, TE, RE, MPIE, and TEIE in SCR_0 Select on-chip clock as clock source using CKE1 and CKE0 in SCR_0 Using SMR_1, select asynchronous mode, 8 data[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 13 of 17 (3) Data Re ceive Rou tine No Ye s Read receive data from RDR_1 and store it in on-chip RAM Transmit receive data without modification Clear RDRF flag in SSR_1 to 0 Wait until RDR_1 finishes receiving data RTE rcv_sci() (4) Data Transfer R[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 14 of 17 6. Program List ing /**************************************************************/ /* SH7145F Application Note */ /* */ /* Function */ /* :SCI1 */ /* */ /* External input clock : 12.5MHz */ /* Internal CPU clock : 50MHz */ /* Internal pe[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 15 of 17 Function : init_sci Operation : Initialize serial (sci1) Asynchronous receive operation -Data : 8bit -Stop bit : 1bit -Parity bit : No **************************************************************/ void init_sci(void) { unsigned long i; P[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 16 of 17 P_SCI1.SSR_1.BIT.RDRF = 0; /* Clear RDRF */ trans_sci(Rev_data[rev_count]); /* Transmit receive data */ rev_count++ ; /* Increment storage address */ return(rev_count); } /*******************************************************************[...]

SH7145F Asynchronous Serial Da ta Transmission/ Reception REJ06B0357-0 100O/Rev.1.0 0 March 2004 Page 17 of 17 1. These materials are intended as a reference to assist our customers in the selection of the Renesas Technology Corp. product best suited to the customer's application; they do not convey any license under any intellectual property [...]