SPRS742L June 2011 – February 2021 F28M35E20B , F28M35H22C , F28M35H52C , F28M35H52C-Q1 , F28M35M22C , F28M35M52C
PRODUCTION DATA
The EPI General-Purpose Mode is designed for high-speed clocked interfaces such as ones communicating with FPGAs and CPLDs. The high-speed clocked interfaces are different from the slower Host Bus interfaces, which have more relaxed timings that are compatible with established protocols like ones used to communicate with 8051 devices. Support of bus cycle framing and precisely controlled clocking are the additional features of the General-Purpose Mode that differentiate the General-Purpose Mode from the 8-bit and 16-bit Host Bus Modes.
Framing allows multiple bus transactions to be grouped together with an output signal called FRAME. The slave device responding to the bus cycles may use this signal to recognize related words of data and to speed up their transfers. The frame lengths are programmable and may vary from 1 to 30 clocks, depending on the clocking mode used.
Precise clocking is accomplished with a dedicated clock output pin (CLK). Devices responding the bus cycles can synchronize to CLK for faster transfers. The clock frequency can be precisely controlled through the Baud Rate Control block. This output clock can be gated or free-running. A gated approach uses a setup-time model in which the EPI clock controls when bus transactions are starting and stopping. A free-running EPI clock requires another method for determining when data is live, such as the frame pin or RD/WR strobes.
These and numerous other aspects of the General-Purpose Mode are controlled through the General-Purpose Configuration Register and the General-Purpose Configuration2 Register. The clocking for the General-Purpose Mode is configured through the EPI Baud Register of the EPI Baud Rate Control block.
See Figure 7-17 for a snapshot of the General-Purpose Mode registers, modes, and features. For more detailed maps of the General-Purpose Mode, see Table 7-3.
EPI PORT NAME | EPI SIGNAL FUNCTION | DEVICE PIN | |||||
---|---|---|---|---|---|---|---|
ACCESSIBLE BY Cortex-M3 | ACCESSIBLE BY C28x | GENERAL-PURPOSE SIGNAL (D8, A20) | GENERAL-PURPOSE SIGNAL (D16, A12) | GENERAL-PURPOSE SIGNAL (D24, A4) | GENERAL-PURPOSE SIGNAL (D30, NO ADDR) | (AVAILABLE GPIOMUX_1 MUXING CHOICES FOR EPI) | |
EPI0S0 | D0 | D0 | D0 | D0 | PH3_GPIO51 | ||
EPI0S1 | D1 | D1 | D1 | D1 | PH2_GPIO50 | ||
EPI0S2 | D2 | D2 | D2 | D2 | PC4_GPIO68 | ||
EPI0S3 | D3 | D3 | D3 | D3 | PC5_GPIO69 | ||
EPI0S4 | D4 | D4 | D4 | D4 | PC6_GPIO70 | ||
EPI0S5 | D5 | D5 | D5 | D5 | PC7_GPIO71 | ||
EPI0S6 | D6 | D6 | D6 | D6 | PH0_GPIO48 | ||
EPI0S7 | D7 | D7 | D7 | D7 | PH1_GPIO49 | ||
EPI0S8 | A0 | D8 | D8 | D8 | PE0_GPIO24 | ||
EPI0S9 | A1 | D9 | D9 | D9 | PE1_GPIO25 | ||
EPI0S10 | A2 | D10 | D10 | D10 | PH4_GPIO52 | ||
EPI0S11 | A3 | D11 | D11 | D11 | PH5_GPIO53 | ||
EPI0S12 | A4 | D12 | D12 | D12 | PF4_GPIO36 | ||
EPI0S13 | A5 | D13 | D13 | D13 | PG0_GPIO40 | ||
EPI0S14 | A6 | D14 | D14 | D14 | PG1_GPIO41 | ||
EPI0S15 | A7 | D15 | D15 | D15 | PF5_GPIO37 | ||
EPI0S16 | A8 | A0 | D16 | D16 | PJ0_GPIO56 | ||
EPI0S17 | A9 | A1 | D17 | D17 | PJ1_GPIO57 | ||
EPI0S18 | A10 | A2 | D18 | D18 | PJ2_GPIO58 | ||
EPI0S19 | A11 | A3 | D19 | D19 | PD4_GPIO20 | PJ3_GPIO59 | |
EPI0S20 | A12 | A4 | D29 | D29 | PD2_GPIO18 | ||
EPI0S21 | A13 | A5 | D21 | D21 | PD3_GPIO19 | ||
EPI0S22 | A14 | A6 | D22 | D22 | PB5_GPIO13 | ||
EPI0S23 | A15 | A7 | D23 | D23 | PB4_GPIO12 | ||
EPI0S24 | A16 | A8 | A0 | D24 | PE2_GPIO26 | ||
EPI0S25 | A17 | A9 | A1 | D25 | PE3_GPIO27 | ||
EPI0S26 | A18 | A10 | A2 | D26 | PH6_GPIO54 | ||
EPI0S27 | A19/RDY | A11/RDY | A3/RDY | D27 | PH7_GPIO55 | ||
EPI0S28 | WR | WR | WR | D28 | PD5_GPIO21 | PJ4_GPIO60 | |
EPI0S29 | RD | RD | RD | D29 | PD6_GPIO22 | PJ5_GPIO61 | |
EPI0S30 | FRAME | FRAME | FRAME | D30 | PD7_GPIO23 | PJ6_GPIO62 | |
EPI0S31 | CLK | CLK | CLK | D31 | PG7_GPIO47 | ||
EPI0S32 | x | x | x | x | PF2_GPIO34 | PC0_GPIO64 | |
EPI0S33 | x | x | x | x | PF3_GPIO35 | PC1_GPIO65 | |
EPI0S34 | x | x | x | x | PE4_GPIO28 | ||
EPI0S35 | x | x | x | x | PE5_GPIO29 | ||
EPI0S36 | x | x | x | x | PB7_GPIO15 | PC3_GPIO67 | |
EPI0S37 | x | x | x | x | PB6_GPIO14 | PC2_GPIO66 | |
EPI0S38 | x | x | x | x | PF6_GPIO38 | PE4_GPIO28 | |
EPI0S39 | x | x | x | x | PG2_GPIO42 | ||
EPI0S40 | x | x | x | x | PG5_GPIO45 | ||
EPI0S41 | x | x | x | x | PG6_GPIO46 |