STANDARD AND PTS INTERRUPTS

14.The transmission will begin. Data is shifted out with the least-significant (rightmost) bit first. Each time a timer match occurs between EPA0_TIME and TIMER1, the EPA0 channel generates an interrupt and the PTS outputs the next bit of data on the pin configured as TXD. When PTSCOUNT decrements to zero, the PTS calls the end-of-PTS interrupt (Figure 5-26). The interrupt service routine should load the next data byte, reload the PTSCOUNT and PTSCON1 registers, clear the TXD bit to create the start bit for the next word to be transmitted, select PTS service for EPA0, and reload both the EPA0_CONTROL and EPA0_TIME registers.

15.To determine when all bytes have been transmitted, create a loop routine to check the status of the TXDDONE flag.

5-53

Page 140
Image 140
Intel 8XC196MC, 8XC196MD, 8XC196MH manual Standard and PTS Interrupts